title: [Chinese waxy elites SW70 and SW22 are revealed to be new multimutants of starch-synthesis enzyme coding genes].
abstract: Waxy maize (wx) is a type of spontaneous starch mutant as compared to wild type foodstuff maize (Wx). The mechanisms underlying waxy maize kernel development are intricate and diversified. Here we characterized the expression of 21 genes belonging to four families, i.e., ADP-glucose pyrophosphorylase (AGPase), starch synthase (SS), starch branching enzyme (SBE) and starch debranching enzyme (DBE) in the developing kernels of waxy maize inbred SW22, SW70 and relative wild type inbred 5003 at 1, 2 and 4 weeks after pollination. Dynamic expression pattern of a number of genes in developing kernels of SW22 were different from that in 5003 and SW70. Besides, obvious presence of wx transcripts in SW22 and SW70 were observed, though at the level lower than that in wild type 5003. Unexpectedly, the transcripts of Gbssllb and isoamylase-type DBE coding gene Iso2 were completely absent in SW22 and SW70. The above observation prompted the hypothesis that partial or complete loss-of-function of Wx, and/or there exist lose-of-function of uncharacterized gene (s) important for amylose synthesis in SW22 such as GbssIIb and Iso2, which may account for the absence of amylose accumulation in SW22.
authors.affiliation: College of Life Sciences, Shanxi Normal University, Linfen 041104.
authors.forename: Xiang Zhen
authors.initials: XZ
authors.lastname: Ding
authors.forename: Ming Ming
authors.initials: MM
authors.lastname: Yang
authors.forename: Bei Guo
authors.initials: BG
authors.lastname: Wang
authors.forename: Gui Qin
authors.initials: GQ
authors.lastname: Yan
authors.forename: Ke
authors.initials: K
authors.lastname: Duan
authors.forename: Jian Hua
authors.initials: JH
authors.lastname: Huang
mesh_terms: D015061:1,4-alpha-Glucan Branching Enzyme / Q000235:genetics; D000688:Amylose / Q000378:metabolism; D017343:Genes, Plant / Q000235:genetics; D051599:Glucose-1-Phosphate Adenylyltransferase / Q000235:genetics; D009154:Mutation; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013214:Starch Synthase / Q000235:genetics; D003313:Zea mays / Q000235:genetics* / Q000378:metabolism
chemical_list: D000688:Amylose; D015061:1,4-alpha-Glucan Branching Enzyme; D013214:Starch Synthase; D051599:Glucose-1-Phosphate Adenylyltransferase