Reference "Molecular cloning and characterization of RGA1 encoding a G protein alpha subunit from rice (Oryza sativa L. IR-36)"

Reference ID

3984

Title

Molecular cloning and characterization of RGA1 encoding a G protein alpha subunit from rice (Oryza sativa L. IR-36)

Source

Plant molecular biology, 1995, vol. 27, pp. 1119-1131

Authors (6)

Seo-H-S	Kim-H-Y
Jeong-J-Y	Lee-S-Y
Cho-M-J	Bahk-J-D

Abstract

A cDNA clone, RGA1, was isolated by using a GPA1 cDNA clone of Arabidopsis
thaliana G protein alpha subunit as a probe from a rice (Oryza sativa L. IR-36)
seedling cDNA library from roots and leaves. Sequence analysis of genomic clone
reveals that the RGA1 gene has 14 exons and 13 introns, and encodes a
polypeptide of 380 amino acid residues with a calculated molecular weight of
44.5 kDa. The encoded protein exhibits a considerable degree of amino acid
sequence similarity to all the other known G protein alpha subunits. A putative
TATA sequence (ATATGA), a potential CAAT box sequence (AGCAATAC), and a cis-
acting element, CCACGTGG (ABRE), known to be involved in ABA induction are found
in the promoter region. The RGA1 protein contains all the consensus regions of G
protein alpha subunits except the cysteine residue near the C-terminus for ADP-
ribosylation by pertussis toxin. The RGA1 polypeptide expressed in Escherichia
coli was, however, ADP-ribosylated by 10 microM [adenylate-32P] NAD and
activated cholera toxin. Southern analysis indicates that there are no other
genes similar to the RGA1 gene in the rice genome. Northern analysis reveals
that the RGA1 mRNA is 1.85 kb long and expressed in vegetative tissues,
including leaves and roots, and that its expression is regulated by light.