Volvox germline-specific genes that are putative targets of RegA repression encode chloroplast proteins

• Published in: Current genetics 1999-12, Vol.36 (6), p.363-370
• Main Authors: Meissner, M, Stark, K, Cresnar, B, Kirk, D.L, Schmitt, R
• Format: Article
• Language: English
• Subjects: Adenosine Triphosphatases - genetics; Algal Proteins - genetics; Algal Proteins - metabolism; Amino Acid Sequence; amino acid sequences; cell differentiation; Chlorophycota; Chlorophyta; Chlorophyta - genetics; Chlorophyta - metabolism; chloroplasts; Chloroplasts - genetics; Chloroplasts - metabolism; Cloning, Molecular; complementary DNA; DNA, Complementary; Electron Transport Complex III; Freshwater; genbank/af110780; genbank/af110781; genbank/af110782; genbank/af110783; genbank/af110784; genbank/af110785; genbank/af110786; genbank/af110787; genbank/af110788; genbank/af110789; genbank/af110790; genbank/af110791; genbank/af110792; genbank/af110793; genbank/af110794; genbank/u22238; genbank/u22329; genbank/u22330; Gene Expression Regulation; genes; genetic regulation; germ cells; Germ Cells - physiology; gonidia; gonidial genes; Iron-Sulfur Proteins - genetics; Iron-Sulfur Proteins - metabolism; Molecular Sequence Data; nuclear genes; nucleotide sequences; Open Reading Frames; Phosphoglycerate Kinase - genetics; Phosphoglycerate Kinase - metabolism; Photosynthetic Reaction Center Complex Proteins - genetics; photosystem I; photosystem II; polypeptides; Protein Biosynthesis; proteins; rega gene; RegA protein; regulator genes; regulatory sequences; Regulatory Sequences, Nucleic Acid; transcription factors; Volvox carteri
• ISSN: 0172-8083; 1432-0983
• DOI: 10.1007/s002940050511

In Volvox carteri, regA acts as a master gene to suppress all germ cell functions in somatic cells. Its product, RegA, has features of a transcriptional repressor. Here we report cDNA sequences representing 15 nuclear genes with properties expected of RegA targets: they are expressed strongly in germ cells and in regA-, but not regA+, somatic cells. Two of them encode polypeptides with no recognizable features, but ten (like three previously sequenced ones) encode chloroplast proteins of known function, and the remaining three encode putative chloroplast proteins of unknown function. This suggests that RegA blocks reproductive development in somatic cells by preventing chloroplast biogenesis, thereby making it impossible for the cells to grow enough to reproduce.