Cloning and overexpression of two cDNAs encoding the low-CO2-inducible chloroplast envelope protein LIP-36 from Chlamydomonas reinhardtii

• Published in: Plant physiology (Bethesda) 1997-05, Vol.114 (1), p.265-273
• Main Authors: Chen, Z.Y. (Southern Regional Research Center, USDA, ARS, New Orleans, LA.), Lavigne, L.L, Mason, C.B, Moroney, J.V
• Format: Article
• Language: English
• Subjects: ADN; Amino Acid Sequence; AMINO ACID SEQUENCES; Amino acids; Animals; Base Sequence; Biochemistry and Enzymology; Biological and medical sciences; CARBON DIOXIDE; Carbon Dioxide - metabolism; Carrier proteins; Carrier Proteins - biosynthesis; Carrier Proteins - genetics; Cell biochemistry; Cell growth; Cell physiology; CHEMICAL COMPOSITION; CHLAMYDOMONAS REINHARDTII; Chlamydomonas reinhardtii - genetics; Chlamydomonas reinhardtii - growth & development; Chlamydomonas reinhardtii - metabolism; Chloroplast Proteins; CHLOROPLASTE; CHLOROPLASTS; Chloroplasts - genetics; Chloroplasts - metabolism; CLONACION; CLONAGE; CLONING; Cloning, Molecular; CLOROPLASTO; CODE GENETIQUE; CODIGO GENETICO; COMPLEMENTARY DNA; COMPOSICION QUIMICA; COMPOSITION CHIMIQUE; DIOXIDO DE CARBONO; DIOXYDE DE CARBONE; DNA; DNA Primers - genetics; DNA, Complementary - genetics; DNA, Protozoan - genetics; DOSAGE EFFECTS; Escherichia coli - genetics; EXPRESION GENICA; EXPRESSION DES GENES; Fundamental and applied biological sciences. Psychology; GENBANK/U75345; GENBANK/U75346; GENE EXPRESSION; Gene Expression Regulation; Genes, Protozoan; GENETIC CODE; GENETIC REGULATION; GENETICA; GENETICS; GENETIQUE; Messenger RNA; MOLECULAR SEQUENCE DATA; Nucleotide sequences; PHOTORESPIRATORY PATHWAY; Plant cells; Plant physiology and development; PLANT PROTEIN; PLANT PROTEINS; Polymerase chain reaction; PROTEINAS; PROTEINAS VEGETALES; PROTEINE; PROTEINE VEGETALE; PROTEINS; Protozoan Proteins - genetics; RESTRICTION MAPPING; Sequence Homology, Amino Acid; VIA METABOLICA FOTORESPIRACION; VOIE METABOLISME PHOTORESPIRATOIRE
• ISSN: 0032-0889; 1532-2548
• DOI: 10.1104/pp.114.1.265

Chlamydomonas reinhardtii, a unicellular green alga, grows photoautotrophically at very low concentrations of inorganic carbon due to the presence of an inducible CO2-concentrating mechanism. During the induction of the CO2-concentrating mechanism at low-CO2 growth conditions, at least five polypeptides that are either absent or present in low amounts in cells grown on high-CO2 concentrations are induced. One of these induced polypeptides with a molecular mass of 36 kD, LIP-36, has been localized to the chloroplast envelope. The protein was purified and the partial internal amino acid sequences were obtained through lys-C digestion. Two cDNAs encoding LIP-36 have been cloned using degenerate primers based on the amino acid sequences. The two genes encoding LIP-36 are highly homologous in the coding region but are completely different in the 5'-end and 3'-end untranslated regions. The deduced protein sequences show strong homology to the mitochondrial carrier protein superfamily, suggesting that LIP-36 is a chloroplast carrier protein. The regulation of the expression of these two genes at high- and low-CO2 growth conditions is also different. Both genes were highly expressed under low-CO2 growth conditions, with the steady-state level of LIP-36 G1 mRNA more abundant. However, neither gene was expressed at high-CO2 growth conditions. The gene products of both clones expressed in Escherichia coli were recognized by an antibody raised against LIP-36, confirming that the two cDNAs indeed encode the C. reinhardtii chloroplast envelope carrier protein LIP-36