CUT1, an arabidopsis gene required for cuticular wax biosynthesis and pollen fertility, encodes a very-long-chain fatty acid condensing enzyme
CUT1, an arabidopsis gene required for cuticular wax biosynthesis and pollen fertility, encodes a very-long-chain fatty acid condensing enzyme
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DOI：
10.1105/tpc.11.5.825
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发表时间：
1999-05-01
期刊：
影响因子：
11.6
通讯作者：
Kunst, L
中科院分区：
文献类型：
--
作者：
Millar, AA;Clemens, S;Kunst, L
陆地植物在其气生表面上分泌一层蜡，这是在陆地环境中生存所必需的。这种蜡由源自超长链脂肪酸（VLCFA）的长链脂肪烃组成。使用拟南芥表达序列标签数据库，我们已经确定了一个基因，命名为CUT1，编码一个VLCFA缩合酶所需的表皮蜡生产。在转基因拟南芥植物中，CUT1的正义抑制导致无蜡（eceriferum）茎和长角果以及条件性雄性不育。扫描电子显微镜显示，这是一个严重的无蜡表型，因为CUT1抑制植物的茎完全没有蜡晶体。此外，对无蜡植物的化学分析表明，茎蜡负荷降低到野生型水平的6%至7%。该值低于报道的任何已知的石蒜属突变体的值。严重的无蜡表型是由于脱羰基和酰基还原蜡生物合成途径的下调。该结果表明，CUT1参与了拟南芥中用于合成所有茎蜡组分的VLCFA前体的产生。在CUT1抑制的植物中，C24链长蜡组分占主导地位，这表明CUT1是C24 VLCFA伸长所必需的。CUT1抑制植物的独特蜡组成以及CUT1在遗传图谱上的位置与任何已知的ECERIFERUM基因座不一致的事实表明，我们已经鉴定了一个参与蜡生物合成的新基因，CUT1是目前唯一已知的在蜡生产中具有明确功能的基因。
Land plants secrete a layer of wax onto their aerial surfaces that is essential for survival in a terrestrial environment. This wax is composed of long-chain, aliphatic hydrocarbons derived from very-long-chain fatty acids (VLCFAs). Using the Arabidopsis expressed sequence tag database, we have identified a gene, designated CUT1, that encodes a VLCFA condensing enzyme required for cuticular wax production. Sense suppression of CUT1 in transgenic Arabidopsis plants results in waxless (eceriferum) stems and siliques as well as conditional male sterility. Scanning electron microscopy revealed that this was a severe waxless phenotype, because stems of CUT1-suppressed plants were completely devoid of wax crystals. Furthermore, chemical analyses of waxless plants demonstrated that the stem wax load was reduced to 6 to 7% of wild-type levels. This value is lower than that reported for any of the known eceriferum mutants. The severe waxless phenotype resulted from the downregulation of both the decarbonylation and acyl reduction wax biosynthetic pathways. This result indicates that CUT1 is involved in the production of VLCFA precursors used for the synthesis of all stem wax components in Arabidopsis. In CUT1-suppressed plants, the C24 chain-length wax components predominate, suggesting that CUT1 is required for elongation of C24 VLCFAs. The unique wax composition of CUT1-suppressed plants together with the fact that the location of CUT1 on the genetic map did not coincide with any of the known ECERIFERUM loci suggest that we have identified a novel gene involved in wax biosynthesis, CUT1 is currently the only known gene with a clearly established function in wax production.