Wheat cysteine proteases triticain alpha, beta and gamma exhibit mutually distinct responses to gibberellin in germinating seeds.
We cloned three novel papain-type cysteine proteases (CPs), triticain alpha, beta and gamma, from 1-d-germinating wheat seeds. Triticain alpha, beta and gamma were constituted with 461, 472 and 365 amino acid residues, respectively, and had Cys-His-Asn catalytic triads as well as signal and propeptide sequences. Triticain gamma contained a putative vacuole-sorting sequence. Phylogenetic analysis showed that these CPs were divided into mutually different clusters. Triticain alpha and gamma mRNAs were expressed in seeds at an early stage of maturation and at the stage of germination 2d after imbibition, while triticain beta mRNA appeared shortly after imbibition. The expression of mRNAs for triticain alpha and gamma was suppressed by uniconazol, a gibberellin synthesis inhibitor. All the three CP mRNAs were strongly expressed in both embryo and aleurone layers. These results suggest that triticain alpha, beta and gamma play differential roles in seed maturation as well as in digestion of storage proteins during germination.
Kiyosaki
Toshihiro
T
Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan.
Asakura
Tomiko
T
Matsumoto
Ichiro
I
Tamura
Tomoko
T
Terauchi
Kaede
K
Funaki
Junko
J
Kuroda
Masaharu
M
Misaka
Takumi
T
Abe
Keiko
K
D000595:Amino Acid Sequence; D003546:Cysteine Endopeptidases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D057056:Cysteine Proteases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D018076:DNA, Complementary / Q000235:genetics; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D018525:Germination / Q000187:drug effects*; D005875:Gibberellins / Q000494:pharmacology*; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D034443:RNA Transport / Q000187:drug effects; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D018749:RNA, Plant / Q000378:metabolism; D012639:Seeds / Q000187:drug effects* / Q000201:enzymology* / Q000235:genetics; D016415:Sequence Alignment; D014908:Triticum / Q000187:drug effects* / Q000201:enzymology* / Q000235:genetics
D018076:DNA, Complementary; D005875:Gibberellins; D010940:Plant Proteins; D012333:RNA, Messenger; D018749:RNA, Plant; D057056:Cysteine Proteases; C000606744:triticain-alpha protein, Triticum aestivum; D003546:Cysteine Endopeptidases