A homolog of the mammalian GTPase Rab2 is present in Arabidopsis and is expressed predominantly in pollen grains and seedlings.

ABSTRACT: Vesicle traffic between the endoplasmic reticulum and the Golgi apparatus in mammals requires the small GTP-binding protein Rab2, but Saccharomyces cerevisiae appears not to have a Rab2 homolog. Here it is shown that the higher plant, Arabidopsis thaliana, contains a gene, At-RAB2, whose predicted product shares 79% identity with human Rab2 protein. Transgenic plants containing fusions between beta-glucuronidase and sequences upstream of At-RAB2 demonstrated histochemical staining predominantly in maturing pollen and rapidly growing organs of germinating seedlings. beta-glucuronidase activity in pollen is first detectable at microspore mitosis and increases thereafter. In this respect, the promoter of At-RAB2 behaves like those of class II pollen-specific genes, whose products are often re

SUBMITTER: Moore I 

PROVIDER: S-EPMC19588 | biostudies-literature | 1997 Jan

REPOSITORIES: biostudies-literature