Expression of an Atriplex nummularia gene encoding a protein homologous to the bacterial molecular chaperone DnaJ.
DnaJ is a 36-kD heat shock protein that functions together with Dnak (Hsp70) as a molecular chaperone in Escherichia coli. We have obtained a cDNA clone from the higher plant Atriplex nummularia that encodes a 46.6-kD polypeptide (ANJ1) with an overall 35.2% amino acid sequence identity with the E. coli DnaJ. ANJ1 has 43.4% overall sequence identity with the Saccharomyces cerevisiae cytoplasmic DnaJ homolog YDJ1/MAS5. Complementation of the yeast mas5 mutation indicated that ANJ1 is a functional homolog of YDJ1/MAS5. The presence of other DnaJ homologs in A. nummularia was demonstrated by the detection of proteins that are antigenically related to the yeast mitochondrial DnaJ homolog SCJ1 and the yeast DnaJ-related protein Sec63. Expression of the ANJ1 gene was compared with that of an A. nummularia Hsp70 gene. Expression of both ANJ1 and Hsp70 transcripts was coordinately induced by heat shock. However, noncoordinate accumulation of ANJ1 and Hsp70 mRNAs occurred during the cell growth cycle and in response to NaCl stress.
Zhu
J K
JK
Center for Plant Environmental Stress Physiology, Purdue University, West Lafayette, Indiana 47907-1165.
Shi
J
J
Bressan
R A
RA
Hasegawa
P M
PM
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics; D001483:Base Sequence; D004247:DNA / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D029968:Escherichia coli Proteins; D005656:Fungal Proteins / Q000235:genetics; D015870:Gene Expression; D005816:Genetic Complementation Test; D050956:HSP40 Heat-Shock Proteins; D006360:Heat-Shock Proteins / Q000235:genetics; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics*; D010944:Plants / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000235:genetics; D017386:Sequence Homology, Amino Acid
D001426:Bacterial Proteins; C494635:DnaJ protein, E coli; D029968:Escherichia coli Proteins; D005656:Fungal Proteins; D050956:HSP40 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D010940:Plant Proteins; D012333:RNA, Messenger; D004247:DNA