Characterization of dnaJ multigene family in the cyanobacterium Synechococcus elongatus PCC 7942.
The genome of the cyanobacterium Synechococcus elongatus PCC 7942 contains four dnaJ homologs, which are classified into three types based on domain structure. Among these, dnaJ1, dnaJ2, and dnaJ3 are essential for normal growth, and hence we analyzed them with a view to characterizing their specificity. Expression analysis indicated that dnaJ2, which encodes type II DnaJ protein, exhibited typical responses to heat and high-light stresses. Their localization and ability to prevent aggregation of luciferase were also diverse, suggesting a possible functional differentiation of these proteins. Since the expression of dnaJ1, which belongs to conserved type I DnaJ, down-regulated under heat stress, the unique structure of DnaJ2 may be involved in stress responses of S. elongatus. Based on phylogenetic analysis, the diverse dnaJ family was assumed to have evolved its own specific functions in each cyanobacterial species.
Sato
Masumi
M
Department of Bioscience, Tokyo University of Agriculture, Tokyo, Japan.
Yamahata
Hikaru
H
Watanabe
Satoru
S
Nimura-Matsune
Kaori
K
Yoshikawa
Hirofumi
H
D020418:Algal Proteins / Q000096:biosynthesis / Q000235:genetics / Q000302:isolation & purification; D001412:Bacillus subtilis / Q000235:genetics / Q000378:metabolism; D015153:Blotting, Western; D017931:DNA Primers; D048028:DNA, Algal / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D050956:HSP40 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D006358:Hot Temperature; D005810:Multigene Family / Q000235:genetics*; D010802:Phylogeny; D010957:Plasmids / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D046940:Synechococcus / Q000235:genetics*; D015854:Up-Regulation
D020418:Algal Proteins; D017931:DNA Primers; D048028:DNA, Algal; D050956:HSP40 Heat-Shock Proteins