• Therefore, the aim of this study was to define a specific role for ABA in the motile green alga, Chlamydomonas reinhardtii , providing evidence that this phytohormone mediates the light-dependent diurnal rhythm of up and down gravitaxis of the algae in the water column. (nature.com)
  • Crystal structure of activated ribulose-1,5-bisphosphate carboxylase/oxyge nase from green alga Chlamydomonas reinhardtii complexed with 2-carboxyarabinitol-1,5-bisphosphate. (bio.net)
  • Our main model organism is the green alga Chlamydomonas reinhardtii . (fau.de)
  • Our research is focused on the analysis of the eyespot apparatus, the „eye", of flagellate green algae. (fau.de)
  • Signals relayed from the eyespot photoreceptors result in alteration of the beating pattern of the flagella, generating a phototactic response. (wikipedia.org)
  • The green algal eyespot apparatus: A primordial visual system and more? (wikipedia.org)
  • Due to their elaborate structures and the presence of retinal-based photoreceptors in some lineages, algal eyespots are thought to play an important role in the evolution of photoreception. (fau.de)
  • The eyespot apparatus (or stigma) is a photoreceptive organelle found in the flagellate or (motile) cells of green algae and other unicellular photosynthetic organisms such as euglenids. (wikipedia.org)
  • The eyespot apparatus of Euglena comprises the paraflagellar body connecting the eyespot to the flagellum. (wikipedia.org)
  • In electron microscopy, the eyespot apparatus appears as a highly ordered lamellar structure formed by membranous rods in a helical arrangement. (wikipedia.org)
  • The eyespot apparatus of green algae utilizes specialized microbial-type rhodopsins as photoreceptors, which act as directly light-gated ion channels. (fau.de)
  • After establishment of an isolation method for the eyespot apparatus in its entire complexity and its core and phosphoproteome (Schmidt et al. (fau.de)
  • The ultrastructure of its eyespot apparatus is depicted briefly in Fig. 1A. (fau.de)
  • Detailed ultrastructural and biophysical analyses have shown that the functional eyespot apparatus involves local specialisations of different subcellular compartments (plasma membrane, cytosol, and chloroplast). (fau.de)
  • The eyespot apparatus of Chlamydomonas reinhardtii in the light microscope (A1, white arrow-head), in the transmission electron microscope (A2) and as a schematic drawing (A3). (fau.de)
  • The ultrastructure of the functional eyespot apparatus is complex and involves local specializations of membranes from different compartments. (fau.de)
  • Eyespots are the simplest and most common "eyes" found in nature, composed of photoreceptors and areas of bright orange-red red pigment granules. (wikipedia.org)
  • Besides photoreceptor proteins, eyespots contain a large number of structural, metabolic and signaling proteins. (wikipedia.org)
  • Structural intact eyespot apparatuses can be isolated by sucrose density gradient centrifugation (B). (fau.de)
  • Reasoning that high-light-induced photo-oxidation likely poses the main threat to photosynthetic algae, here the initial investigation focused on the effect of ABA on the photosynthetic efficiency of C. reinhardtii by measuring the ability of treated algae to deplete their growing media of dissolved HCO 3 − under different light levels. (nature.com)
  • Several aspects of the photoresponse have previously been analyzed in volvocine algae, particularly in the unicellular alga Chlamydomonas. (uni-bielefeld.de)
  • At the posterior pole, the eyespots are tiny or absent, making the corresponding cells appear to be blind. (uni-bielefeld.de)
  • We show that exogenous ABA significantly altered the HCO 3 − uptake of Chamydomonas reinhardtii in a light-intensity-dependent manner. (nature.com)
  • Under the light microscope, eyespots appear as dark, orange-reddish spots or stigmata. (wikipedia.org)
  • Molecular characterization and gene expression of lhcb5 gene encoding CP26 in the light-harvesting complex II of Chlamydomonas reinhardtii. (bio.net)
  • The responsiveness to light is consistent with an anterior-to-posterior size gradient of eyespots. (uni-bielefeld.de)
  • This asymmetric positioning of the eyespot in the cell is essential for proper phototaxis. (wikipedia.org)
  • The FA2 gene of Chlamydomonas encodes a NIMA family kinase with roles in cell cycle progression and microtubule severing during deflagellation. (bio.net)
  • Kinesin-II is not essential for mitosis and cell growth in Chlamydomonas. (bio.net)
  • The Antarctic psychrophile, Chlamydomonas subcaudata, is deficient in state I state II transitions. (bio.net)
  • The eyespot apparatus (or stigma) is a photoreceptive organelle found in the flagellate or (motile) cells of green algae and other unicellular photosynthetic organisms such as euglenids. (wikipedia.org)
  • The single chloroplast of the unicellular alga Chlamydomonas reinhardtii contains an orange carotenoid pigment spot that functions in phototaxis. (cellimagelibrary.org)
  • Chlamydomonas is unicellular and reflects the ancestral state of the group, while Volvox is multicellular and has evolved numerous innovations including germ-soma differentiation, sexual dimorphism, and complex morphogenetic patterning. (nih.gov)
  • The multicellular volvocine species Volvox carteri exhibits many hallmarks of complex multicellularity including complete germ-soma division of labor, asymmetric cell divisions, coordinated tissue-level morphogenesis, and dimorphic sexes-none of which have obvious analogs in its closest unicellular relative, the model alga Chlamydomonas reinhardtii . (biomedcentral.com)
  • The most critical eyespot proteins are the photoreceptor proteins that sense light. (wikipedia.org)
  • Besides photoreceptor proteins, eyespots contain a large number of structural, metabolic and signaling proteins. (wikipedia.org)
  • This asymmetric positioning of the eyespot in the cell is essential for proper phototaxis. (wikipedia.org)
  • In contrast, Chlamydomonas phototaxis is mediated by archaeal-type rhodopsins. (wikipedia.org)
  • The species Chlamydomonas reinhardtii and Volvox carteri represent extremes in morphological diversity within the Volvocine clade. (nih.gov)
  • The divergence time between the common ancestor of C. reinhardtii and multicellular volvocine species is estimated at around 250 MY [ 6 ], though the fossil record for green algae is sparse and complicated by homoplasy that makes definitive taxonomic affiliation and time calibration difficult [ 7 ]. (biomedcentral.com)
  • Eyespots are the simplest and most common "eyes" found in nature, composed of photoreceptors and areas of bright orange-red red pigment granules. (wikipedia.org)
  • Vegetative phase V. carteri are spheroids of several hundred microns diameter which are organized in a simple radially symmetric multicellular body plan with just two cell types: ~ 2000 small sterile biflagellate somatic cells that are similar in size to a Chlamydomonas cell, and 12-16 large aflagellate reproductive cells called gonidia (Fig. 2 a-e). (biomedcentral.com)
  • Baidukova O, Oppermann J, Kelterborn S, Fernandez Lahore RG, Schumacher D, Evers H, Kamrani YY, Hegemann P. Gating and ion selectivity of Channelrhodopsins are critical for photo-activated orientation of Chlamydomonas as shown by in vivo point mutation. (chlamycollection.org)