RRC ID 50277
著者 Hirashima T, Toyoshima M, Moriyama T, Sato N.
タイトル Evolution of the Phosphatidylcholine Biosynthesis Pathways in Green Algae: Combinatorial Diversity of Methyltransferases.
ジャーナル J Mol Evol
Abstract Phosphatidylcholine (PC) is one of the most common phospholipids in eukaryotes, although some green algae such as Chlamydomonas reinhardtii are known to lack PC. Recently, we detected PC in four species in the genus Chlamydomonas: C. applanata NIES-2202, C. asymmetrica NIES-2207, C. debaryana NIES-2212, and C. sphaeroides NIES-2242. To reveal the PC biosynthesis pathways in green algae and the evolutionary scenario involved in their diversity, we analyzed the PC biosynthesis genes in these four algae using draft genome sequences. Homology searches suggested that PC in these species is synthesized by phosphoethanolamine-N-methyltransferase (PEAMT) and/or phosphatidylethanolamine-N-methyltransferase (PEMT), both of which are absent in C. reinhardtii. Recombinant PEAMTs from these algae showed methyltransferase activity for phosphoethanolamine but not for monomethyl phosphoethanolamine in vitro, in contrast to land plant PEAMT, which catalyzes the three methylations from phosphoethanolamine to phosphocholine. This suggested an involvement of other methyltransferases in PC biosynthesis. Here, we characterized the putative phospholipid-N-methyltransferase (PLMT) genes of these species by genetic and phylogenetic analysis. Complementation assays using a PC biosynthesis-deficient yeast suggested that the PLMTs of these algae can synthesize PC from phosphatidylethanolamine. These results indicated that the PC biosynthesis pathways in green algae differ from those of land plants, although the enzymes involved are homologous. Phylogenetic analysis suggested that the PEAMTs and PLMTs in these algae were inherited from the common ancestor of green algae. The absence of PC biosynthesis in many Chlamydomonas species is likely a result of parallel losses of PEAMT and PLMT in this genus.
巻・号 86(1)
ページ 68-76
公開日 2018-1-1
DOI 10.1007/s00239-017-9826-4
PII 10.1007/s00239-017-9826-4
PMID 29330556
MeSH Amino Acid Sequence / genetics Base Sequence / genetics Biological Evolution Chlamydomonas / genetics* Chlamydomonas / metabolism Chlorophyta / genetics Chlorophyta / metabolism Cloning, Molecular / methods Ethanolamines / metabolism Evolution, Molecular Methyltransferases / genetics Methyltransferases / metabolism Phosphatidylcholines / biosynthesis* Phosphatidylcholines / genetics* Phosphatidylethanolamine N-Methyltransferase / metabolism Phosphatidylethanolamines / genetics Phosphatidylethanolamines / metabolism Phylogeny
IF 1.821
引用数 0
リソース情報
藻類 NIES-2202 NIES-2207 NIES-2212 NIES-2242