Identification of an allele of VAM3/SYP22 that confers a semi-dwarf phenotype in Arabidopsis thaliana
Identification of an allele of VAM3/SYP22 that confers a semi-dwarf phenotype in Arabidopsis thaliana
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DOI：
10.1093/pcp/pci146
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发表时间：
2005-08-01
影响因子：
4.9
通讯作者：
Takahashi, T
中科院分区：
文献类型：
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作者：
Ohtomo, I;Ueda, H;Takahashi, T
拟南芥短茎和中脉（ssm）突变体由于茎节间和叶片伸长的缺陷而表现出半矮化和波浪叶表型。此外，这些异常不能通过外源性植物激素来恢复。ssm最初被鉴定为生态型哥伦比亚（Col-0）的单隐性突变体，但是遗传杂交实验已经揭示，该突变体表型被另一个在生态型兰茨贝格直立（Ler）中而不是在Col-0中有功能的基因恢复。图位克隆的基因是有缺陷的ssm突变体中发现了一个小的缺失，在第六内含子的基因编码的syntaxin，VAM 3/SYP 22，这已经牵连在小泡运输到液泡。由于缩短的第六内含子的缺陷性剪接，该突变似乎导致在推导的VAM 3/SYP 22多肽序列中的肽插入。值得注意的是，当与野生型Ler基因组相比时，野生型Col-0基因组具有单碱基对缺失，导致SYP 23中的移码突变，SYP 23是与VAM 3/SYP 22具有最高已知同源性的基因。这些发现表明，VAM 3/SYP 22和SYP 23有重叠的功能，这些syntaxins介导的囊泡运输是很重要的芽形态建成。
The short stem and midrib (ssm) mutants of Arabidopsis thaliana show both semi-dwarf and wavy leaf phenotypes due to defects in the elongation of the stem internodes and leaves. Moreover, these abnormalities cannot be recovered by exogenous phytohormones. ssm was originally identified as a single recessive mutant of the ecotype Columbia (Col-0), but genetic crossing experiments have revealed that this mutant phenotype is restored by another gene that is functional in the ecotype Landsberg erecta (Ler) and not in Col-0. Map-based cloning of the gene that is defective in ssm mutants has uncovered a small deletion in the sixth intron of a gene encoding a syntaxin, VAM3/SYP22, which has been implicated in vesicle transport to the vacuole. This mutation appears to cause a peptide insertion in the deduced VAM3/SYP22 polypeptide sequence due to defective splicing of the shortened sixth intron. Significantly, when compared with the wild-type Ler genome, the wild-type Col-0 genome has a single base pair deletion causing a frameshift mutation in SYP23, a gene with the highest known homology to VAM3/SYP22. These findings suggest that VAM3/SYP22 and SYP23 have overlapping functions and that the vesicle transport mediated by these syntaxins is important for shoot morphogenesis.