Immunolocalization of the G protein alpha subunit encoded by the GPA1 gene in Arabidopsis

Weiss, C. A., Huang, H., Ma, H. (November 1993) Immunolocalization of the G protein alpha subunit encoded by the GPA1 gene in Arabidopsis. Plant Cell, 5 (11). pp. 1513-28. ISSN 1040-4651 (Print)

Abstract

Heterotrimeric GTP binding proteins (G proteins) are important signal transducers in lower eukaryotes and in animal cells. In plants, the occurrence of GTP binding proteins has been reported, but their biological function remains unclear. Two genes coding for G protein alpha subunits have been cloned: GPA1 in Arabidopsis and TGA1 in tomato. To gain some insights into the function of GPA1, we describe an extensive immunolocalization of GPalpha1, the gene product of GPA1, during Arabidopsis development. Our results show that the GPalpha1 is present through all stages of development and in all organs examined, with the exception of mature seeds. It is expressed in roots, floral stem, rosette leaves, cauline leaves, flowers, and seed pods. Interestingly, the level of GPalpha1 protein is higher in immature organs than in mature organs. GPalpha1 is present at a high level in the root meristem and elongation zone, in the shoot and floral meristems, and in the leaf primordium and floral organ (sepal, petal, stamen, and gynoecium) primordia. During flower development, dividing microspores, but not mature pollen, show high levels of GPalpha1. During pollination, GPalpha1 is present in the growing pollen tubes. The protein is also present in nectaries and developing ovules and, after fertilization, in developing embryos. In mature tissue, GPalpha1 is preferentially found in the vascular system but is also present in other cell types. The complexity of the GPalpha1 localization pattern suggests that GPalpha1 might be involved in different signaling pathways depending on the developmental stage.

Item Type: Paper
Uncontrolled Keywords: Amino Acid Sequence Arabidopsis/chemistry/ genetics GTP-Binding Proteins/ chemistry/genetics Genes, Plant Immunoblotting Molecular Sequence Data Plant Proteins/analysis/ genetics/immunology Pollen/physiology Seeds/chemistry/growth & development
Subjects: organism description > plant > Arabidopsis
bioinformatics > genomics and proteomics > genetics & nucleic acid processing > protein structure, function, modification > protein types > G protein
bioinformatics > genomics and proteomics > genetics & nucleic acid processing > protein structure, function, modification > protein types > GTP binding protein
CSHL Authors:
Communities: CSHL labs
Depositing User: Matt Covey
Date: November 1993
Date Deposited: 08 Apr 2016 19:48
Last Modified: 08 Apr 2016 19:48
PMCID: PMC160382
Related URLs:
URI: https://repository.cshl.edu/id/eprint/32589

Actions (login required)

Administrator's edit/view item Administrator's edit/view item