Acyl-CoA synthetases from Physcomitrella, rice and Arabidopsis different substrate preferences but common regulation by MS188 in sporopollenin synthesis

• Published in: Planta Vol. 250; no. 2; pp. 535 - 548
• Main Authors: Li, Yue-Ling, Zhang, Yan-Fei, Li, Dan-Dan, Shi, Qiang-Sheng, Lou, Yue, Yang, Zhong-Nan, Zhu, Jun
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Science + Business Media 01.08.2019; Springer Berlin Heidelberg; Springer Nature B.V
• Subjects: Agriculture; Amino Acid Sequence; Arabidopsis; Arabidopsis - enzymology; Arabidopsis - genetics; Arabidopsis - growth & development; Arabidopsis - ultrastructure; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Biomedical and Life Sciences; Biopolymers - biosynthesis; Bryopsida - enzymology; Bryopsida - genetics; Bryopsida - growth & development; Bryopsida - ultrastructure; Carotenoids - biosynthesis; Coenzyme A Ligases - genetics; Coenzyme A Ligases - metabolism; Complementation; Conservation; Divergence; Ecology; Evolution; Evolutionary conservation; Fatty acids; Fertility; Forestry; Gene expression; Gene regulation; Genes; Genes, Reporter; Life Sciences; Monomers; Mutation; ORIGINAL ARTICLE; Oryza; Oryza - enzymology; Oryza - genetics; Oryza - growth & development; Oryza - ultrastructure; Phenotypes; Phylogeny; Physcomitrella; Plant Infertility; Plant Proteins - genetics; Plant Proteins - metabolism; Plant Sciences; Pollen; Pollen - enzymology; Pollen - genetics; Pollen - growth & development; Pollen - ultrastructure; Promoters; Rice; Sequence Alignment; Substrate preferences; Substrate Specificity; Substrates; Synthesis; Transcription Factors - genetics; Transcription Factors - metabolism; Yeast; Pollen development; Exine; Acyl-CoA synthetase; MALE STERILE 188; Sporopollenin
• ISSN: 0032-0935; 1432-2048
• DOI: 10.1007/s00425-019-03189-0

Sporopollenin is the major constituent of spore and pollen exines. In Arabidopsis, acyl-CoA synthetase 5 (ACOS5) is an essential enzyme for sporopollenin synthesis, and its orthologues are PpACOS6 from the moss Physcomitrella and OsACOS12 from monocot rice. However, knowledge regarding the evolutionary conservation and divergence of the ACOS gene in sporopollenin synthesis remains limited. In this study, we analysed the function and regulation of PpACOS6 and OsACOS12. A complementation test showed that OsACOS12 driven by the ACOS5 promoter could partially restore the male fertility of the acos5 mutant in Arabidopsis, while PpACOS6 did not rescue the acos5 phenotype. ACOS5, PpACOS6 and OsACOS12 all complemented the acyl-CoA synthetase-deficient yeast strain (YB525) phenotype, although they exhibited different substrate preferences. To understand the conservation of sporopollenin synthesis regulation, we constructed two constructs with ACOS5 driven by the OsACOS12 or PpACOS6 promoter. Both constructs could restore the fertility of acos5 plants. The MYB transcription factor MS188 from Arabidopsis directly regulates ACOS5. We found that MS188 could also bind the promoters of OsACOS12 and PpACOS6 and activate the genes driven by the promoters, suggesting that the transcriptional regulation of these genes was similar to that of ACOS5. These results show that the ACOS gene promoter region from Physcomitrella, rice and Arabidopsis has been functionally conserved during evolution, while the chain lengths of fatty acid-derived monomers of sporopollenin vary in different plant species.