Norico Yamada

Universität Konstanz | Uni-Konstanz · Department of Biology

Dinoflagellates of the family Kryptoperidiniaceae, known as "dinotoms", possess diatom-derived endosymbionts and contain individuals at three successive evolutionary stages: a transiently maintained kleptoplastic stage; a stage containing multiple permanently maintained diatom endosymbionts; and a further permanent stage containing a single diatom...

Endosymbiosis is a widespread and ecologically significant phenomenon in the marine environment. How these endosymbiotic partners evolve into an organism with a new organelle is still mostly unknown and requires investigation into modern symbioses. Dinotoms, dinoflagellates with evolutionarily intermediate diatom plastids, are considered excellent...

Durinskia capensis is a kleptoplastic dinoflagellate species from high intertidal marine rock pools, which can use a variety of diatoms for photosynthesis. However, very few of the diatoms permit indefinite survival of the dinoflagellate and rbcL sequences show that D. capensis isolated from nature contains one of two closely related Nitzschia spec...

Dinothrix paradoxa and Gymnodinium quadrilobatum are benthic dinoflagellates possessing diatom-derived tertiary plastids, so-called dinotoms. Due to the lack of available genetic information, their phylogenetic relationship remains unknown. In this study, sequencing of 18S ribosomal DNA (rDNA) and the rbcL gene from temporary cultures isolated from...

A monophyletic group of dinoflagellates, called ‘dinotoms’, are known to possess evolutionarily intermediate plastids derived from diatoms. The diatoms maintain their nuclei, mitochondria, and the endoplasmic reticulum in addition with their plastids, while it has been observed that the host dinoflagellates retain the diatoms permanently by control...

A new species of marine sand‐dwelling dinoflagellate, Plagiodinium ballux N. Yamada, Dawut, R. Terada & T. Horiguchi is described from a deep (36 m) seafloor off Takeshima Island, Kagoshima Prefecture, Japan in the subtropical region of the northwest Pacific. The species is thecate and superficially resembles species of Prorocentrum, but possesses...

Dinoflagellates are known to possess chloroplasts of multiple origins derived from a red alga, a green alga, haptophytes, or diatoms. The monophyletic "dinotoms" harbor a chloroplast of diatom origin, but their chloroplasts are polyphyletic belonging to one of four genera: Chaetoceros, Cyclotella, Discostella, or Nitzschia. It has been speculated t...

Compared to planktonic species, there is little known about the ecology, physiology, and existence of benthic dinoflagellates living in sandy beach or seafloor environments. In a previous study, we discovered 132,173-cyclopheophorbide a enol (cPPB-aE) from sand-dwelling benthic dinoflagellates. This enol had never been detected in phytoplankton des...

Although chlorophyll degradation pathways in higher plants have been well studied, little is known about the mechanisms of chlorophyll degradation in microalgae. In this article, we report the occurrence of a chlorophyll a derivative that has never been discovered in photosynthetic organisms. This chlorophyll derivative emits no fluorescence and ha...

A new athecate dinoflagellate, Bispinodinium angelaceum N. Yamada et Horiguchi gen. et sp. nov., is described from a sand sample collected on the seafloor at a depth of 36 m off Mageshima Island, subtropical Japan. The dinoflagellate is dorsiventrally compressed and axi-symmetric along the sulcus. The morphology resembles that of the genus Amphidin...

The individual role of the outer dynein arm light chains in the molecular mechanisms of ciliary movements in response to second messengers, such as Ca2+ and cyclic nucleotides, is unclear. We examined the role of the gene termed the outer dynein arm light chain 1 (LC1) gene of Paramecium tetraurelia (ODAL1), a homologue of the outer dynein arm LC1...