Abstract

DnaJ (Hsp40), a heat shock protein, is a molecular chaperones responsive to various environmental stress. To analyze the protective role of DnaJ, we obtained sense transgenic Arabidopsis plants that constitutively expressed elevated levels of DnaJ. In this study, sense transgenic plants show large thinner, fade color and malformed leaves, as well as less floss of back leaves. Plants with enhanced levels of DnaJ in their transgenic sense lines exhibited tolerance to NaCl stress. Under 120 mM NaCl, root length was higher in transgenic sense plants than wild-type plants. In vitro expression system, DnaJ protein shows tolerance to high NaCl. These results suggest that over-expression of DnaJ can confer NaCl-stress tolerance.

Key words: DnaJ (Hsp40), NaCl, sense-transgenic plants, in vitro expression.

Abbreviation

Abbreviations: DNA, Deoxyribonucleic acid; cDNA, complementary DNA; Hsp, heat shock protein; PCR, polymerase chain reaction; RT-PCR, reverse transcriptase – PCR; CTAB, cetyl trimethyl ammonium bromide; dCTP,deoxycytidine 5’- triphosphates; SDS, sodium dodesyl sulfate; RE, relative enrichment; EDTA, ethylene diamine tetraacetic acid; PAGE, polyacrylamide gel electrophoresis