Two Closely Related Genes of Arabidopsis Encode Plastidial Cytidinediphosphate Diacylglycerol Synthases Essential for Photoautotrophic Growth

Abstract

Cytidinediphosphate diacylglycerol synthase (CDS) catalyzes the formation of cytidinediphosphate diacylglycerol, an essential precursor of anionic phosphoglycerolipids like phosphatidylglycerol or -inositol. In plant cells, CDS isozymes are located in plastids, mitochondria, and microsomes. Here, we show that these isozymes are encoded by five genes in Arabidopsis (Arabidopsis thaliana). Alternative translation initiation or alternative splicing of CDS2 and CDS4 transcripts can result in up to 10 isoforms. Most of the cDNAs encoding the various plant isoforms were functionally expressed in yeast and rescued the nonviable phenotype of the mutant strain lacking CDS activity. The closely related genes CDS4 and CDS5 were found to encode plastidial isozymes with similar catalytic properties. Inactivation of both genes was required to obtain Arabidopsis mutant lines with a visible phenotype, suggesting that the genes have redundant functions. Analysis of these Arabidopsis mutants provided further independent evidence for the importance of plastidial phosphatidylglycerol for structure and function of thylakoid membranes and, hence, for photoautotrophic growth.

Common and Distinct Functions of Arabidopsis Class A1 and A2 Heat Shock Factors in Diverse Abiotic Stress Responses and Development

“…According to the functions reported in previous studies (Kelly et al, 2003;Rossel et al, 2006;Simpson et al, 2009;Haselier et al, 2010;Moellering and Benning, 2010;Zhao et al, 2010;Valluru and Van den Ende, 2011), these genes may contribute to maintenance of cellular homeostasis during prolonged heat stress. In addition, HSFA2, when expressed at high levels, functioned in a similar manner to the HSFA1s regulating a large number of chaperones and cochaperones, such as HSP101, HSP90, HSP70B, HSP70-15, HSP60-3B, small HSPs, MITOCHONDRIAL GRPE2 (MGE2), and ROTAMASE FKBP2 (ROF2; Fig.…”

Isolation and characterization of a phosphatidylglycerophosphate phosphatase1, PGPP1, in Chlamydomonas reinhardtii

“…C. reinhardtii has two CDSs, annotated as CDS1 and CDS2 (Table 1) (Riekhof et al, 2005). A. thaliana has two plastidic CDSs, CDS4 and CDS5, which function redundantly in chloroplasts (Haselier et al, 2010) in addition to ER-localized CDS1, CDS2 and CDS3 (Zhou et al, 2013).…”

“…Haselier et al, 2010;Zhou et al, 2013) Haselier et al, 2010Zhou et al, 2013) Haselier et al, 2010Zhou et al, 2013) PRESTO (to Y.N), Japan Science and Technology Agency, and the core budget of Institute of Plant and Microbial Biology, Academia Sinica (to Y.N).…”

Function of polar glycerolipids in flower development in Arabidopsis thaliana

“…Both genes showed increased transcript levels in pistils. The product PA is dephosphorylated by plastidic PA phosphatases, lipid phosphate phosphatase  (LPP), LPP1, and LPP2 [19], or converted to cytidine diphosphate-diacylglycerol (CDP-DAG) by CDP-DAG synthases CDS4 and CDS5 [20] for subsequent PG synthesis by PGP synthase 1 (PGP1) [21,22] or formation of inositol lipids. The expression of genes for PG biosynthesis was higher in pistils than other organs, although that of LPPs had no floralorgan-specificity.…”

“…CDSs, which all encode functional enzymes to complement a relevant yeast mutant [20]. CDS1-CDS3 are ER membrane-localized [41] and CDS4 and CDS5 are plastidic [20].…”