Table 1.
Representative photoreceptors in eukaryotic algae
| Photoreceptor classes | Chromophore | Domain composition | Representative algae | Reference |
|---|---|---|---|---|
| Phytochrome | Bilins | PAS-GAF-PHY-(PAS)2-HKD-REC | Micromonas pusilla | Duanmu et al. 2014 |
| PAS-GAF-PHY-PAS-HKD-REC | Cyanophora paradoxa | Duanmu et al. 2014 | ||
| PAS-GAF-PHY-PAS-PKC-RING | Guillardia theta | Duanmu et al. 2014 | ||
| PAS-GAF-PHY-HKD-REC | Thalassiosira pseudonana | Fortunato et al. 2016 | ||
|
| ||||
| Cryptochrome | FAD+MTHF(?) | Cry-DASH: PHR | Chlamydomonas reinhardtii | Beel et al. 2012 |
| FAD+MTHF (?) | Plant Cry: PHR-DAS | Coccomyxa subellipsoidea | Fortunato et al. 2015 | |
| FAD+MTHF | Plant Cry-like: dAS-PHR | Coccomyxa subellipsoidea | Fortunato et al. 2015 | |
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| Phototropin | FMN | LOV-LOV-STKD | Chlamydomonas reinhardtii | Huang & Beck 2003 |
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| BLUF-protein | FMN | Aureochrome: bZIP-LOV | Vaucheria frigida | Takahashi et al. 2007 |
| Bilin+FMN(?) | Neochrome: PHY-LOV-LOV-STKD | Mougeotia scalaris | Suetsugu et al. 2005 | |
| FAD | PAC: BLUF-AC-BLUF-AC | Euglena gracilis | Iseki et al. 2002 | |
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| Rhodopsin | Retinal | Channelrhodopsin: Rh/ChR-Reg.domain | Chlamydomonas reinhardtii | Nagel et al. 2002 |
| Enzymerhodopsin: Rh-HisK-REC-AC/GC | Chlamydomonas reinhardtii | Kateriya et al. 2004 | ||
| Light driven ion pump: Rh/AR | Acetabularia acetabulum | Tsunoda et al. 2006 | ||
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| UVR8 | Trp | (RCC1)7 | Chlamydomonas reinhardtii | Tilbrook et al. 2016 |
Representative photoreceptor classes and the domain composition according to the Pfam database (due to space limit, not all characterized algal photoreceptors are included in this table). Domain abbreviations are: AC/GC, adenylyl or guanylyl cyclase; AR, Acetabularia rhodopsins; BLUF, blue-light sensors using flavin adenine dinucleotide; bZIP, basic region/leucine zipper; CCE, cryptochrome C-terminal extension; ChR, channelrhodopsin; Cry-DASH, cryptochrome of Drosophila, Arabidopsis, Synechococcus, Homo; DAS: DQXVP Acidic STAESS motif; dAS, refers to a DAS motif missing the DQXVP; FAD, flavin adenine dinucleotide; FMN, flavin mononucleotide; GAF, cGMP-specific phosphodiesterases, adenylyl cyclases and FhlA; HisK, histidine kinase; HKD, Histidine Kinase A domain and H-ATPase-c domain; LOV, light-oxygen-voltage; MTHF: 5-methenyltetrahydrofolate; PAC, photoactivated adenylyl cyclase; PAS, Period-Arnt-Sim domain; PHY, phytochrome photosensory domain; PHR, photolyase homology region; RCC1, regulator of chromosome condensation repeat 1; REC, response regulator receiver; Reg.domain, regulatory domain; Rh, rhodopsin; RING, really interesting new gene; STKD, serine/threonine kinase domain; Trp, tryptophan; UVR8, Ultraviolet Resistance Locus 8.