Submitted to: Acta Botanica Sinica
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/8/1998
Publication Date: N/A
Citation: Interpretive Summary: The biological responses of plants to environmental stress are not well understood. Stress, caused by heat, cold, drought, or pathogen attack, can significantly reduce crop productivity. Early in the stress response there are changes in the chemical composition of plants. A better understanding of these chemical changes should allow the development of strategies to avoid losses in productivity caused by stress. The genetic material responsible for one of the chemicals that plants make when stressed was isolated and analyzed. The times and places where the genetic information are expressed were defined. The plant genetic material was compared to similar genetic material from animals and microbes in order to identify regions of importance. This information will be important in designing crop plants that will be less damaged by environmental stress, through plant breeding or biotechnology.
Technical Abstract: The nucleotide sequence of a cDNA clone from Arabidopsis thaliana L., ecotype Columbia, was determined. The open reading frame encoded a protein, AtJ3, which was highly homologous to DnaJ protein of E. coli. The predicted amino acid sequence of AtJ3 contained J-domain, G or GF domain, cystine-rich Zn finger-like sequence, which were all characteristic of this class of DnaJ homologues. And the C-terminal of AtJ3 was -CAQQ, a farnesylation motif. Using primers based on the cDNA, the corresponding gene AtJ3 was isolated and sequenced. The structure of this gene consists of six exons interrupted by five introns. The results of Southern analysis indicated that AtJ3 was a single structure gene. AtJ3 was constitutively expressed in cotyledons, leaves, roots, flowers, and siliques based on Northern analysis. Heat shock at 35 degrees C led to increase in mRNA expression in leaves.