RT Journal T1 CHLAMYDOMONAS REINHARDTII SEC23 PARALOGS AND THEIR PHYLOGENETIC RELATIONSHIPS A1 M. Aksoy A1 A. R. Grossman A1 Ö. Musul JF Journal of Animal and Plant Sciences JO JAPS SN 1018-7081 VO 32 IS 5 SP 1261 OP 1273 YR 2022 FD 2022/10/05 DO DOI https://doi.org/10.36899/JAPS.2022.5.0533 AB

C. reinhardtii has two putative SEC23 genes, CrSEC23A and CrSEC23B. The encoded polypeptides are only ~18.9% identical, suggesting that they might have different functions. It is not clear whether SEC23 paralogs have same or different functions in diverse organisms. Interestingly, our alignment and homology modeling showed that CrSEC23B does not have the conserved SEC24 binding motif (VFR), but instead appears to have an LPA motif in the same position. While LPA might be part of a novel SEC24 binding motif, CrSEC23B might have an alternate function that is either associated with or independent of COPII. Our results also show SEC23 orthologs in various organisms have variations in the putative SEC24 binding motif. Phylogenetic analyses place the SEC23 orthologs into two clusters that we designated group A (conventional; CrSEC23A-like orthologs) and group B (unconventional; CrSEC23B-like orthologs). Our results suggest that many photosynthetic organisms have a divergent SEC23 paralog. This divergence is not seen in animals. We hypothesize that divergent (unconventional) SEC23 paralogs might be the result of gene duplication and divergence that may facilitate specific aspects of trafficking. Since we only identified the B-like proteins in photosynthetic lineages, we hypothesize that B-like proteins may not have been present in the common ancestor involved in the primary endosymbiotic event.

K1 Chlamydomonas reinhardtii, SEC23 paralogs, gene duplication, secretory pathway, COPII PB Pakistan Agricultural Scientists Forum LK https://thejaps.org.pk/AbstractView.aspx?mid=Biot-21-0049