Expression pattern of a chloroplast NADPH-dependent thioredoxin reductase in Chlorella vulgaris during hardening and its interaction with 2-Cys peroxiredoxin.
A chloroplastic NADPH-dependent thioredoxin reductase gene was identified from Chlorella vulgaris and designated CvNTRC. Mature CvNTRC protein (mCvNTRC) was expressed in Escherichia coli, and it showed both NADPH-dependent thioredoxin reductase (NTR) and thioredoxin (Trx)-like dithiol-disulfide oxidoreductase activities. The transcript of CvNTRC increased throughout 24-h hardening, whereas the encoded protein amount and total NTR activity decreased once and then increased during hardening. By in vitro pull-down assay, a 21.2-kDa protein bound to mCvNTRC was isolated and identified as a 2-Cys peroxiredoxin (2-Cys Prx) based on the N-terminal sequence. These data suggest that CvNTRC is maintained at a constant level during hardening and functions as an antioxidant with 2-Cys Prx in the acquisition of freezing tolerance of Chlorella.
Machida
Takeshi
T
Department of Bioscience and Biotechnology, Graduate School of Bioresources and Bioenvironmental Sciences, Kyushu University, Fukuoka, Japan.
Kato
Eri
E
Ishibashi
Akiko
A
Sato
Jun-ichi
J
Kawasaki
Shinji
S
Niimura
Youichi
Y
Honjoh
Ken-ichi
K
Miyamoto
Takahisa
T
D000595:Amino Acid Sequence; D001483:Base Sequence; D002708:Chlorella / Q000201:enzymology* / Q000502:physiology*; D002736:Chloroplasts / Q000201:enzymology*; D018076:DNA, Complementary / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D005615:Freezing; D005786:Gene Expression Regulation; D006639:Histidine / Q000378:metabolism; D008969:Molecular Sequence Data; D009249:NADP / Q000378:metabolism*; D054464:Peroxiredoxins / Q000378:metabolism*; D014176:Protein Biosynthesis; D013880:Thioredoxin-Disulfide Reductase / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D013879:Thioredoxins / Q000378:metabolism; D014158:Transcription, Genetic
D018076:DNA, Complementary; D006639:Histidine; D013879:Thioredoxins; D009249:NADP; D054464:Peroxiredoxins; D013880:Thioredoxin-Disulfide Reductase