TY - JOUR
T1 - Vacuolar processing enzyme plays an essential role in the crystalline structure of glutelin in rice seed
AU - Kumamaru, Toshihiro
AU - Uemura, Yuji
AU - Inoue, Yoshimi
AU - Takemoto, Yoko
AU - Siddiqui, Sadar Uddin
AU - Ogawa, Masahiro
AU - Hara-Nishimura, Ikuko
AU - Satoh, Hikaru
N1 - Funding Information:
This work was supported partly by a grant-in-aid for Scientific Research on Priority Areas (B) from the Ministry of Education, Culture, Sports, Science and Technology of Japan (1213826) and grants from the Bio-oriented Technology Research Advanced Institution (BRAIN), and the Ministry of Agriculture, Forest and Fish of Japan (MP1108).
PY - 2010/1
Y1 - 2010/1
N2 - To identify the function of genes that regulate the processing of proglutelin, we performed an analysis of glup3 mutants, which accumulates excess amounts of proglutelin and lack the vacuolar processing enzyme (VPE). VPE activity in developing seeds from glup3 lines was reduced remarkably compared with the wild type. DNA sequencing of the VPE gene in glup3 mutants revealed either amino acid substitutions or the appearance of a stop codon within the coding region. Microscopic observations showed that α-globulin and proglutelin were distributed homogeneously within glup3 protein storage vacuoles (PSVs), and that glup3 PSVs lacked the crystalline lattice structure typical of wild-type PSVs. This suggests that the processing of proglutelin by VPE in rice is essential for proper PSV structure and compartmentalization of storage proteins. Growth retardation in glup3 seedlings was also observed, indicating that the processing of proglutelin influences early seedling development. These findings indicate that storage of glutelin in its mature form as a crystalline structure in PSVs is required for the rapid use of glutelin as a source of amino acids during early seedling development. In conclusion, VPE plays an important role in the formation of protein crystalline structures in PSVs.
AB - To identify the function of genes that regulate the processing of proglutelin, we performed an analysis of glup3 mutants, which accumulates excess amounts of proglutelin and lack the vacuolar processing enzyme (VPE). VPE activity in developing seeds from glup3 lines was reduced remarkably compared with the wild type. DNA sequencing of the VPE gene in glup3 mutants revealed either amino acid substitutions or the appearance of a stop codon within the coding region. Microscopic observations showed that α-globulin and proglutelin were distributed homogeneously within glup3 protein storage vacuoles (PSVs), and that glup3 PSVs lacked the crystalline lattice structure typical of wild-type PSVs. This suggests that the processing of proglutelin by VPE in rice is essential for proper PSV structure and compartmentalization of storage proteins. Growth retardation in glup3 seedlings was also observed, indicating that the processing of proglutelin influences early seedling development. These findings indicate that storage of glutelin in its mature form as a crystalline structure in PSVs is required for the rapid use of glutelin as a source of amino acids during early seedling development. In conclusion, VPE plays an important role in the formation of protein crystalline structures in PSVs.
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U2 - 10.1093/pcp/pcp165
DO - 10.1093/pcp/pcp165
M3 - Article
C2 - 19933265
AN - SCOPUS:74549197626
SN - 0032-0781
VL - 51
SP - 38
EP - 46
JO - Plant and Cell Physiology
JF - Plant and Cell Physiology
IS - 1
ER -