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Organogenesis at the shoot meristem requires a delicate balance between stem cell specification and differentiation. In Arabidopsis thaliana, WUSCHEL (WUS) is a key factor promoting stem cell identity, whereas the CLAVATA (CLV1, CLV2, and CLV3) loci appear to promote differentiation by repressing WUS expression. In a screen for mutations modifying...
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... plants appeared superficially wild type in phenotype. Scanning electron microscopy analysis of cna-1 shoot meri- stems revealed that the meristems of 12-d-old cna-1 plants are significantly larger than wild-type meristems (see Supplemental Figure 1 online; Table 1). The effect, if any, of cna-1 on shoot meristem size in 24-d-old plants is reduced compared with earlier developmental time points (Table 1). ...
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... clv cna-1 double mutants with these clv alleles developed shoot meristems that were enlarged in comparison with clv meristems, even at early stages of vegetative develop- ment (see Supplemental Figure 2 online ; Figures 1A to 1C and 2A to 2F, Tables 2 and 3). Early in development, clv3-2 cna-1 plants had visible, enlarged meristems and also occasionally lacked identifiable young organ primordia around portions of the pe- riphery of the shoot meristem ( Figures 1C, 1E, and 2A to 2D). This loss-of-organogenesis phenotype exhibited strong variation in expressivity early in development, although at later stages we consistently observed apices with older primordia but not younger primordia (see Supplemental Figure 2 online; Figures 1 and 2). ...
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... in development, clv3-2 cna-1 plants had visible, enlarged meristems and also occasionally lacked identifiable young organ primordia around portions of the pe- riphery of the shoot meristem ( Figures 1C, 1E, and 2A to 2D). This loss-of-organogenesis phenotype exhibited strong variation in expressivity early in development, although at later stages we consistently observed apices with older primordia but not younger primordia (see Supplemental Figure 2 online; Figures 1 and 2). The loss of organ formation was not always uniform around the periphery of the shoot meristem (Figures 1 and 2). ...
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... loss-of-organogenesis phenotype exhibited strong variation in expressivity early in development, although at later stages we consistently observed apices with older primordia but not younger primordia (see Supplemental Figure 2 online; Figures 1 and 2). The loss of organ formation was not always uniform around the periphery of the shoot meristem (Figures 1 and 2). Moreover, a plant that had initiated no or few leaves during vegetative development could later initiate flower primordia ( Figures 2B to 2D). ...
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... with the loss of organogenesis in clv3-2 cna-1 plants, we also observed that the entire apices of clv3-2 cna-1 plants eventually differentiated into organs. Subtle changes in the topography of the shoot apical meristems of clv3-2 cna-1 plants ;8 d old were observed by scanning electron microscopy, with an indentation appearing in the center of the meristem ( Figures 1A and 1B). Starting at approximately day 15, carpeloid and filamentous organs often formed in the center of the clv3-2 cna-1 meristems ( Figures 1F to 1H), leaving a ring of more meristem-like tissue. ...
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... changes in the topography of the shoot apical meristems of clv3-2 cna-1 plants ;8 d old were observed by scanning electron microscopy, with an indentation appearing in the center of the meristem ( Figures 1A and 1B). Starting at approximately day 15, carpeloid and filamentous organs often formed in the center of the clv3-2 cna-1 meristems ( Figures 1F to 1H), leaving a ring of more meristem-like tissue. clv3-2 cna-1 apices eventually differenti- ated across the entire apical region ( Figures 1F to 1J). ...
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The CLAVATA1 (CLV1), CLV2, and CORYNE (CRN) receptors in Arabidopsis thaliana maintain cell proliferation in shoot apical meristems by restricting expression of the transcription factor WUSCHEL (WUS). Previously characterized receptor mutants generate extra fruit and floral organs that are proposed to arise from enlarged floral meristems (FMs). We...
During the development of multicellular organisms, organogenesis and pattern formation depend on formative divisions to specify and maintain pools of stem cells. In higher plants, these activities are essential to shape the final root architecture because the functioning of root apical meristems and the de novo formation of lateral roots entirely r...
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... Two Arabidopsis ATHB15 mutants were also studied: corona-1 (cna-1; Green et al., 2005) and its Col-0 WT background (provided by G. Morelli, CREA-GB, Italy), and incurvata4-1 (icu4-1; Ochando et al., 2006) and its En-2 WT background (provided by J.L. Micol, Universidad Miguel Hernańdez, Spain). Twenty plants of each genotype were cultured at 24°C ± 2°C in growth chamber under a 16/8h light/dark photoperiod. ...
... Arabidopsis HD-Zip III proteins are involved in vasculature development (Prigge et al., 2005); therefore, we analyzed the vascular phenotype in WT and pat-mutant tomato seedlings. Compared to the WT, hypocotyl cross sections of pat plantlets showed a disorganized vasculature (Supplementary Figures 5A, B), although the symmetry of the vascular bundles appeared to be conserved. ...
... The phylogenetic analysis indicated that Solyc03g120910 represents the tomato ortholog of HB15 in Arabidopsis. To evaluate whether HB15 variants showed phenotypes resembling those found in pat in tomato, we characterized targeted vegetative and reproductive traits in cna-1, a loss-offunction mutant showing a A606V substitution in a conserved domain (Green et al., 2005) and icu4-1, a gain of function variant showing a point mutation affecting the microRNA complementarity site (Ochando et al., 2006). About 22% of the pat mutant seedlings showed defects in cotyledon number and/or morphology (Olimpieri et al., 2007; Figure 7A); a similar phenotype was found in about 10% of the icu4-1 seedlings ( Figure 7B), but no cotyledon alterations were observed in cna-1. ...
Parthenocarpy allows fruit set independently of fertilization. In parthenocarpic-prone tomato genotypes, fruit set can be achieved under pollen-limiting environmental conditions and in sterile mutants. Parthenocarpy is also regarded as a quality-related trait, when seedlessness is associated with positive fruit quality aspects. Among the different sources of genetic parthenocarpy described in tomato, the parthenocarpic fruit (pat) mutation is of particular interest because of its strong expressivity, high fruit set, and enhanced fruit quality. The complexity of the pat “syndrome” associates a strong competence for parthenocarpy with a complex floral phenotype involving stamen and ovule developmental aberrations. To understand the genetic basis of the phenotype, we mapped the pat locus within a 0.19-cM window of Chr3, comprising nine coding loci. A non-tolerated missense mutation found in the 14th exon of Solyc03g120910, the tomato ortholog of the Arabidopsis HD-Zip III transcription factor HB15 (SlHB15), cosegregated with the pat phenotype. The role of SlHB15 in tomato reproductive development was supported by its expression in developing ovules. The link between pat and SlHB15 was validated by complementation and knock out experiments by co-suppression and CRISPR/Cas9 approaches. Comparing the phenotypes of pat and those of Arabidopsis HB15 mutants, we argued that the gene plays similar functions in species with fleshy and dry fruits, supporting a conserved mechanism of fruit set regulation in plants.
... Regarding the pivotal members that orchestrate the destiny of meristematic tissues, the myb TF AS1 plays a crucial role in guiding leaf patterning and facilitating stem cell functions in Arabidopsis [34]; the homeobox TF STM is essential for the formation of the shoot apical meristem during embryonic development [35]; the auxin response TF MP is required to establish the embryonic axis by determining the root and vascular structures [36]; and the Homeodomain-Leucine Zipper TF CNA regulates stem cell definition and organ formation [37]. Additionally, these TFs potentially interact, suggesting that the loss of apical dominance observed post-HS treatment might be associated with the co-upregulation of these critical TFs that govern the fate of meristematic tissues. ...
Climate change-induced heat stress (HS) increasingly threatens potato (Solanum tuberosum L.) production by impacting tuberization and causing the premature sprouting of tubers grown during the hot season. However, the effects of post-harvest HS on tuber sprouting have yet to be explored. This study aims to investigate the effects of post-harvest HS on tuber sprouting and to explore the underlying transcriptomic changes in apical bud meristems. The results show that post-harvest HS facilitates potato tuber sprouting and negates apical dominance. A meticulous transcriptomic profiling of apical bud meristems unearthed a spectrum of differentially expressed genes (DEGs) activated in response to HS. During the heightened sprouting activity that occurred at 15–18 days of HS, the pathways associated with starch metabolism, photomorphogenesis, and circadian rhythm were predominantly suppressed, while those governing chromosome organization, steroid biosynthesis, and transcription factors were markedly enhanced. The critical DEGs encompassed the enzymes pivotal for starch metabolism, the genes central to gibberellin and brassinosteroid biosynthesis, and influential developmental transcription factors, such as SHORT VEGETATIVE PHASE, ASYMMETRIC LEAVES 1, SHOOT MERISTEMLESS, and MONOPTEROS. These findings suggest that HS orchestrates tuber sprouting through nuanced alterations in gene expression within the meristematic tissues, specifically influencing chromatin organization, hormonal biosynthesis pathways, and the transcription factors presiding over meristem fate determination. The present study provides novel insights into the intricate molecular mechanisms whereby post-harvest HS influences tuber sprouting. The findings have important implications for developing strategies to mitigate HS-induced tuber sprouting in the context of climate change.
... These regulatory genes include CLAVATA1-3 (CLV1-3) and WUSCHEL (WUS) as well as WIGGUM (WIG) and ULTRAPETALA (ULT) (Running et al. 1998;Schoof et al. 2000;Fletcher 2001; Galli and Gallavotti 2016). In addition, a number of studies have demonstrated that members of different gene families have critical impact on floral organogenesis, involving SQUAMOSA promoter binding protein-like (SPL) transcription factors (Ta et al. 2017) and class III homeodomain-leucine zipper (HD-ZIP III) transcription factors (Green et al. 2005;Williams et al. 2005;Jung and Park 2007). Of which, SPL family members SPL3/4/5 positively regulate the floral meristem (FM) identity transition in Arabidopsis (Lal et al. 2011;Xu et al. 2016), while the accumulation of SPL18 transcript is considered to be associated with number of spikelets and secondary branches of panicle in rice (Xie et al. 2006). ...
... For example, miR156 targets SPL genes, being reported to control floral meristem identity or axillary meristem initiation in Arabidopsis and rice (Lal et al. 2011;Xu et al. 2016;Ta et al. 2017). As for miR166 family, they specifically regulate HD-ZIP III transcription factor family genes, thereby functioning in shoot apical meristem (SAM) or lateral meristem (LM) initiation and development (Green et al. 2005;Williams et al. 2005;Jung and Park 2007). MiR172 has been wellcharacterized to regulate floral organ identity through directly targeting APETALA2 (AP2) genes, and overexpression of miR172 disrupts the specification of floral organ identity in Arabidopsis (Aukerman and Sakai 2003). ...
... MiR166, another well-defined miRNA family in land plants, has been characterized to repress the expressions of HD-ZIP III transcription factor family genes (Jia et al. 2015). Increasing evidence shows that miR166 and its target HD-ZIP III genes play the overlapping, distinct, and antagonistic roles in SAM or LM formation (Green et al. 2005;Williams et al. 2005;Jung and Park 2007). Different from lacking discernible phenotypic abnormalities in loss-of-function mutants of four individual members except REV, gain-of-function mutants show enlarged meristems in Arabidopsis Byrne 2006;Duclercq et al. 2011;Zhang and Zhang 2012). ...
Magnolia species commonly have three tepals in a single floral whorl. Magnolia polytepala, a native species in China, possesses three tepals in outer three floral whorls, but approximately six tepals arranged in the fourth floral whorl, forming the unique multi-tepal trait. To understand the miRNA-mediated molecular mechanism governing its floral architecture, floral buds from normal petaloid tepal primordia differentiation period (S1), multi-tepal primordia differentiation period (S2), and tepal primordia differentiation finished period (S3) were collected for high-throughput sequencing and then to investigate microRNAs relevant to multi-tepal formation in M. polytepala. A total of 54 conserved and 116 novel miRNAs were identified in differentiated floral buds of three developmental stages, of which 16 and 21 were significantly differentially expressed, respectively. The biological functions of differentially expressed miRNAs were explored via computationally predicting target mRNAs, finally identifying a total of 436 mRNAs expressing during multi-tepal differentiation process. Co-expression analysis of miRNAs and target mRNAs implied that miRNAs potentially played important roles in multi-tepal traits of M. polytepala via regulating their target gene’s expression; in particular, miR156/SPL, miR166/HD-ZIP III, miR397/LAC, and Mp_n-miR105/TKI1 regulatory cascades were putatively involved in floral organ primordia initiation and development, while Mp_n-miR7/CDC48A module probably functioned in cell division and proliferation of multi-tepal differentiation. Our results could facilitate the understanding of miRNA-mediated molecular regulatory mechanism underlying the floral phenotype of M. polytepala at post-transcriptional level and also benefit for finding a new path altering horticultural traits of Magnolia species.
... CUC1 and CUC2 are involved in regulating the formation of SAM during embryogenesis by activating STM and KNAT6 [72]. Other important TFs, including ATH1, ATHBs, REV, MAIN, and LEU, are also involved in the regulation of the initiation, maintenance, and development of SAM [74][75][76][77]. In this study, the levels of expression of WUS, KNAT6, CUC2, ATH1, ATHB15, and REV were all substantially enhanced in the somatic embryos (S3). ...
Low propagation rate is the primary problem that limits industry development of tree peony. In this study, a highly efficient regeneration system for tree peony using somatic embryogenesis (SE) was established. The transcriptomes of zygotic embryo explants (S0), non-embryonic callus (S1), embryonic callus (S2), somatic embryos (S3), and regenerated shoots (S4) were analyzed to determine the regulatory mechanisms that underlie SE in tree peony. The differentially expressed genes (DEGs) were identified in the pairwise comparisons of S1-vs-S2 and S1-vs-S3, respectively. The enriched DEGs were primarily involved in hormone signal transduction, stress response and the nucleus (epigenetic modifications). The results indicated that cell division, particularly asymmetric cell division, was enhanced in S3. Moreover, the genes implicated in cell fate determination played central roles in S3. Hormone signal pathways work in concert with epigenetic modifications and stress responses to regulate SE. SERK, WOX9, BBM, FUS3, CUC, and WUS were characterized as the molecular markers for tree peony SE. To our knowledge, this is the first study of the SE of tree peony using transcriptome sequencing. These results will improve our understanding of the molecular mechanisms that underly SE in tree peony and will benefit the propagation and genetic engineering of this plant.
... Two types of xylems, PX and metaxylem, are patterned centripetally in vascular tissues, which are controlled by endodermis-derived mobile microRNAs (miRNAs) miR165 and miR166 (Carlsbecker et al., 2010). To generate the positional information, these two mobile miRNAs move from endodermis into stele, creating a dosage gradient which maintains the spatial expression pattern of many xylem patterning genes, including the Class III HOMEODOMAIN LEU-ZIPPER (HD-ZIPIII) family proteins PHABULOSA (PHB), PHAVOLUTA (PHV), ATHB8, ATHB15, and REVOLUTA (REV; Talbert et al., 1995;Baima et al., 2001;McConnell et al., 2001;Green et al., 2005;Prigge et al., 2005;Miyashima et al., 2011). The expression of miR165/166 in endodermis is controlled by two GRAS transcription factors SCARECROW (SCR) and SHORT-ROOT (SHR; Carlsbecker et al., 2010;Yu et al., 2010;Hao and Cui, 2012). ...
Cell wall lignification is a key step in forming functional endodermis and protoxylem in plant roots. Lignified casparian strips (CS) in endodermis and tracheary elements of protoxylem are essential for selective absorption and transport of water and nutrients. Although multiple key regulators of CS and protoxylem have been identified, the spatial information that drives the developmental shift to root lignification remains unknown. Here, we found that brassinosteroid signaling plays a key role in inhibiting root lignification in the root elongation zone. The inhibitory activity of brassinosteroid signaling occurs partially through the direct binding of BRASSINAZOLE-RESISTANT 1 (BZR1) to SHORT-ROOT (SHR), repressing the SHR-mediated activation of downstream genes that are involved in root lignification. Upon entering the mature root zone, brassinosteroid signaling declines rapidly, which releases SHR activity and initiates root lignification. Our results provide a mechanistic view of the developmental transition to cell wall lignification in Arabidopsis thaliana roots.
... When their function is suppressed, midrib formation is abnormal and leaf shape becomes distorted (Yip et al., 2016). Given that HD-ZIP III transcription factors ATHB8, ATHB15, and REVOLUTA are essential for procambial cell specification and vasculature development, the observation that HD-ZIP III proteins function in specifying moss waterconducting tissues further suggests that shared molecular mechanisms underpin conducting tissue development in convergent plant organs (Kang and Dengler, 2002;Ohashi-Ito et al., 2002;Green et al., 2005;Prigge et al., 2005;Donner et al., 2009) and therefore that these mechanisms may have evolved before the divergence between bryophytes and vascular plants. Nonetheless, further research on midrib development is needed to uncover the regulatory circuits underlying the morphological differences between juvenile and adult leaves. ...
Specialized photosynthetic organs have appeared several times independently during the evolution of land plants. Phyllids, the leaf-like organs of bryophytes such as mosses or leafy liverworts, display a simple morphology, with a small number of cells and cell types and lack typical vascular tissue which contrasts greatly with flowering plants. Despite this, the leaf structures of these two plant types share many morphological characteristics. In this review, we summarize the current understanding of leaf morphogenesis in the model moss Physcomitrium patens, focusing on the underlying cellular patterns and molecular regulatory mechanisms. We discuss this knowledge in an evolutionary context and identify parallels between moss and flowering plant leaf development. Finally, we propose potential research directions that may help to answer fundamental questions in plant development using moss leaves as a model system.
... Judicious manipulation of a regulatory gene can increase the activity of an entire biosynthetic pathway [26]. HD-ZIP III, a TF, is involved in stem cell maintenance, meristem growth, and organ morphogenesis in A. thaliana [27] and in metabolite biosynthesis. HD-ZIP is associated with terpenoid biosynthesis and is a candidate gene for regulating Eu-rubber accumulation in Eucommia ulmoides [28]. ...
The study of somatic embryogenesis can provide insight into early plant development. We previously obtained LaMIR166a-overexpressing embryonic cell lines of Larix kaempferi (Lamb.) Carr. To further elucidate the molecular mechanisms associated with miR166 in this species, the transcriptional profiles of wild-type (WT) and three LaMIR166a-overexpressing transgenic cell lines were subjected to RNA sequencing using the Illumina NovaSeq 6000 system. In total, 203,256 unigenes were generated using Trinity de novo assembly, and 2467 differentially expressed genes were obtained by comparing transgenic and WT lines. In addition, we analyzed the cleaved degree of LaMIR166a target genes LaHDZ31–34 in different transgenic cell lines by detecting the expression pattern of LaHdZ31–34, and their cleaved degree in transgenic cell lines was higher than that in WT. The downstream genes of LaHDZ31–34 were identified using Pearson correlation coefficients. Yeast one-hybrid and dual-luciferase report assays revealed that the transcription factors LaHDZ31–34 could bind to the promoters of LaPAP, LaPP1, LaZFP5, and LaPHO1. This is the first report of gene expression changes caused by LaMIR166a overexpression in Japanese larch. These findings lay a foundation for future studies on the regulatory mechanism of miR166.
... ult1 displays an enlarged SAM similar to that of clv mutants, associated with an enlargement of WUS, CLV1 and CLV3 expression domains, suggesting that ULT1, like the CLV pathway, acts to restrict the size of the OC (Carles et al., 2004;Fletcher, 2001;Monfared et al., 2013). (Green et al., 2005;Prigge et al., 2005;Williams et al., 2005). Although SAM developmental defects observed in various mutant backgrounds were shown to be due to an increase in WUS expression both quantitatively and spatially, suggesting that PHB, PHV and CNA act to restrict the size of the OC (Williams et al., 2005(Williams et al., , 2005, more recent data reported that these HD-ZIP III genes allow stem cell recovery even in wus mutant background (Huang et al., 2015;Lee and Clark, 2015;Mandel et al., 2016). ...
In plants, the development of aerial organs is indeterminate: it takes place throughout their lifespan. In contrast, the development of floral organs is determinate in Arabidopsis thaliana, each flower has the same number of floral organs. This difference in development is due to the maintenance or not of the pool of stem cells present in the stem cell niches, the meristems. During my thesis I showed that the transcriptional regulator VIP3 contributes to the regulation of the switch from indeterminate to determinate in flowers. This also revealed that the control of flower termination is not as robust as classically thought. Because VIP3 is also involved in the regulation of epigenetic marks and response to external mechanical stimuli, this work opens new questions on the role of mechanical signals in indeterminacy. On a more technical standpoint, the analysis of shoot development suffers from a lack of imaging methods with high temporal resolution and in-depth optical sectioning. During the last decade, light sheet microscopy has emerged as a competitive imaging modality in developmental biology. However, in plants, the technique has mainly been used in roots because of limits in the microscope design. During my thesis, I developed protocols allowing the imaging of aerial organs in A. thaliana using a novel light sheet set-up (Phaseview Alpha3) where shoot samples can be observed while in water. I set up an imaging pipeline from sample mounting to quantitative analysis, with a focus on local dynamics of microtubules in cotyledon epidermis in relation to cell shape. Altogether, this work provides both conceptual and technical prospects for future quantitative projects in plant development.
... The results of numerous studies indicate a relationship between other regulators of SAM development-HD-ZIPIII TFsand the WUS gene. Analysis of plants with the cna1 mutation in the CORONA (CNA) gene encoding TF of the HD-ZIPIII family, plants with the jba1D mutation, which are characterized by overexpression of the miRNA gene (miR166G, the HD-ZIPIII genes repressor) and the combination of these mutations with the wus-1 mutation suggests negative regulation of WUS expression by HD-ZIPIII factors [56,57]. Nevertheless, direct binding of HD-ZIPIII TFs PHABULOSA (PHB), PHAVOLUTA (PHV), and REVOLUTA (REV) to the WUS locus during shoot regeneration, and their interaction with type B ARABIDOPSIS RESPONSE REGULATOR (ARR) (ARR1 and ARR2) TFs, direct WUS activators (see below), has been shown. ...
... WUS also affects the flower phenotype, acting not only as a regulator of the development of flower meristem, but also as a direct participant in the development of flower organs. For example, WUS expression was found in developing anthers between locules and later during the development of the stamen, in peripheral anther cells [56,102]. The anthers of plants with loss of WUS function often have smaller or malformed lobes as compared to wild-type anthers, and do not open [103]. ...
WOX (WUSCHEL-RELATED HOMEOBOX) is a family of homeodomain-containing transcription factors in plants. WOX proteins maintain the activity of different types of meristems and regulate the formation of plant organs, controlling cell proliferation and differentiation. Study of the WOX family is important for the development of plant transformation and genome editing techniques. Here we review the functions of the WOX transcription factors as well as their targets, partners, and regulators. The WOX family can be divided into three phylogenetically distinct clades: so-called ancient, intermediate, and WUS clade; each clade is covered in a separate section. The WOX genes of Arabidopsis thaliana are described most comprehensively, with their orthologs in other plant species also considered. Summary tables with the described targets, regulators and partners of WOX family members are provided.
... HD-ZIP is also responsible for regulating plant cell differentiation and participating in the development of apical meristems, embryos, and vascular systems [15]. There are five family members of Arabidopsis HD-ZIP [13], due to differences in domains and expression patterns, each member plays different role [23][24][25]. The PCN gene in poplar belongs to the HD-ZIP subfamily and has a role in regulating xylem cell differentiation [26]. ...
HD-ZIP is a unique type of transcription factor in plants, which are closely linked to the regulation of plant growth and development, the response to abiotic stress, and disease resistance. However, there is little known about the HD-ZIP gene family of pepper. In this study, 40 HD-ZIP family members were analyzed in the pepper genome. The analysis indicated that the introns number of Ca-HD-ZIP varied from 1 to 17; the number of amino acids was between 119 and 841; the theoretical isoelectric point was between 4.54 and 9.85; the molecular weight was between 14.04 and 92.56; most of them were unstable proteins. The phylogenetic tree divided CaHD-ZIP into 4 subfamilies; 40 CaHD-ZIP genes were located on different chromosomes, and all of them contained the motif 1; two pairs of CaHD-ZIP parallel genes of six paralogism genes were fragment duplications which occurred in 58.28~88.24 million years ago. There were multiple pressure-related action elements upstream of the start codon of the HD-Z-IP family. Protein interaction network proved to be coexpression phenomenon between ATML1 (CaH-DZ22, CaHDZ32) and At4g048909 (CaHDZ12, CaHDZ31), and three regions of them were highly homology. The expression level of CaHD-ZIP gene was different with tissues and developmental stages, which suggested that CaHD-ZIP may be involved in biological functions during pepper progress. In addition, Pepper HD-ZIP I and II genes played a major role in salt stress. CaHDZ03, CaHDZ 10, CaHDZ17, CaHDZ25, CaHDZ34, and CaHDZ35 were significantly induced in response to salt stress. Notably, the expression of CaHDZ07, CaHDZ17, CaHDZ26, and CaHDZ30, homologs of Arabidopsis AtHB12 and AtHB7 genes, was significantly upregulated by salt stresses. CaHDZ03 possesses two closely linked ABA action elements, and its expression level increased significantly at 4 h under salt stress. qRT-P-CR and transcription analysis showed that the expression of CaHDZ03 and CaHDZ10 was upregulated under short-term salt stress, but CaHDZ10 was downregulated with long-term salt stress, which provided a theoretical basis for research the function of Ca-HDZIP in response to abiotic stress.
