Species	Reference gene ID	Possible function	Papers / DOI
Arabidopsis	At3g53920	Sigma factors are initiation factors that promote the attachment of plastid-encoded RNA polymerase (PEP) to specific initiation sites and are then released.	Characterization of Arabidopsis plastid sigma-like transcription factors SIG1, SIG2 and SIG3.; 2003; DOI: 10.1023/a:1022095017355; PMID: 12602869; https://pubmed.ncbi.nlm.nih.gov/12602869/
Arabidopsis	At1g08540	Required for the transition of plastids into chloroplasts by coordinating nuclear and chloroplastic genomes under light conditions.	No verified direct reference in this release
Arabidopsis	At2g36990	Sigma factors are initiation factors that promote the attachment of plastid-encoded RNA polymerase (PEP) to specific initiation sites and are then released.	A nuclear-encoded sigma factor, Arabidopsis SIG6, recognizes sigma-70 type chloroplast promoters and regulates early chloroplast development in cotyledons.; 2005; DOI: 10.1111/j.1365-313x.2005.02362.x; PMID: 15807777; https://pubmed.ncbi.nlm.nih.gov/15807777/ | Characterization of soldat8, a suppressor of singlet oxygen-induced cell death in Arabidopsis seedlings.; 2009; DOI: 10.1093/pcp/pcp036; PMID: 19273469; https://pubmed.ncbi.nlm.nih.gov/19273469/ | Interaction of the pentatricopeptide-repeat protein DELAYED GREENING 1 with sigma factor SIG6 in the regulation of chloroplast gene expression in Arabidopsis cotyledons.; 2010; DOI: 10.1111/j.1365-313x.2010.04304.x; PMID: 20626654; https://pubmed.ncbi.nlm.nih.gov/20626654/