Two Independent Plastid accD Transfers to the Nuclear Genome of Gnetum and Other Insights on Acetyl-CoA Carboxylase Evolution in Gymnosperms
| Autor: | Edi Sudianto, Shu-Miaw Chaw |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
0106 biological sciences
Plastid localization Nuclear gene Gnetum fatty acid biosynthesis Biology 010603 evolutionary biology 01 natural sciences Evolution Molecular 03 medical and health sciences accD plastid-to-nucleus gene transfer plastid localization evolution Genetics Homomeric Plastids Plastid Repeated sequence Gene Ecology Evolution Behavior and Systematics Phylogeny 030304 developmental biology Cell Nucleus 0303 health sciences Acetyl-CoA carboxylase biology.organism_classification Mutagenesis Insertional Cycadopsida acetyl-CoA carboxylase (ACCase) Acetyl-CoA Carboxylase Research Article |
| Zdroj: | Genome Biology and Evolution |
| ISSN: | 1759-6653 |
| Popis: | Acetyl-CoA carboxylase (ACCase) is the key regulator of fatty acid biosynthesis. In most plants, ACCase exists in two locations (cytosol and plastids) and in two forms (homomeric and heteromeric). Heteromeric ACCase comprises four subunits, three of them (ACCA–C) are nuclear encoded (nr) and the fourth (ACCD) is usually plastid encoded. Homomeric ACCase is encoded by a single nr-gene (ACC). We investigated the ACCase gene evolution in gymnosperms by examining the transcriptomes of newly sequenced Gnetum ula, combined with 75 transcriptomes and 110 plastomes of other gymnosperms. AccD-coding sequences are elongated through the insertion of repetitive DNA in four out of five cupressophyte families (except Sciadopityaceae) and were functionally transferred to the nucleus of gnetophytes and Sciadopitys. We discovered that, among the three genera of gnetophytes, only Gnetum has two copies of nr-accD. Furthermore, using protoplast transient expression assays, we experimentally verified that the nr-accD precursor proteins in Gnetum and Sciadopitys can be delivered to the plastids. Of the two nr-accD copies of Gnetum, one dually targets plastids and mitochondria, whereas the other potentially targets plastoglobuli. The distinct transit peptides, gene architectures, and flanking sequences between the two Gnetum accDs suggest that they have independent origins. Our findings are the first account of two distinctly targeted nr-accDs of any green plants and the most comprehensive analyses of ACCase evolution in gymnosperms to date. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|