The TIP GROWTH DEFECTIVE1 S-acyl transferase regulates plant cell growth in Arabidopsis
The TIP GROWTH DEFECTIVE1 S-acyl transferase regulates plant cell growth in Arabidopsis
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DOI：
10.1105/tpc.105.031237
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发表时间：
2005-09-01
期刊：
影响因子：
11.6
通讯作者：
Grierson, CS
中科院分区：
文献类型：
--
作者：
Hemsley, PA;Kemp, AC;Grierson, CS
拟南芥根尖生长缺陷1（TIP 1）影响整个植物的细胞生长，并对根毛生长有特别强的影响。我们通过图位克隆和突变表型互补鉴定了TIP 1。TIP 1编码锚蛋白重复序列蛋白，具有DHHC Cys丰富结构域，在根、叶、花序茎和花组织中表达。TIP 1在酵母（酿酒酵母）和人类（智人）中的两个同源物已显示具有S-酰基转移酶（也称为棕榈酰转移酶）活性。S-酰化是一种可逆的疏水性蛋白质修饰，其提供对蛋白质疏水性的快速、灵活的控制，并影响蛋白质与膜的缔合、信号转导和细胞内的囊泡运输。我们表明TIP 1与棕榈酸酯酰基结合，它可以挽救酵母S-酰基转移酶突变体akr 1 Delta的形态、温度敏感性和酵母酪蛋白激酶2定位缺陷，并且野生型拟南芥根中酰化的抑制可以重现TIP 1（-）突变表型。我们的研究结果表明，S-酰化是必不可少的正常植物细胞的生长，并确定植物S-酰基转移酶，一个必不可少的研究工具，如果我们要了解这个重要的，可逆的脂质修饰在植物细胞中的运作。
TIP GROWTH DEFECTIVE1 (TIP1) of Arabidopsis thaliana affects cell growth throughout the plant and has a particularly strong effect on root hair growth. We have identified TIP1 by map-based cloning and complementation of the mutant phenotype. TIP1 encodes an ankyrin repeat protein with a DHHC Cys-rich domain that is expressed in roots, leaves, inflorescence stems, and floral tissue. Two homologues of TIP1 in yeast ( Saccharomyces cerevisiae) and human ( Homo sapiens) have been shown to have S-acyl transferase ( also known as palmitoyl transferase) activity. S-acylation is a reversible hydrophobic protein modification that offers swift, flexible control of protein hydrophobicity and affects protein association with membranes, signal transduction, and vesicle trafficking within cells. We show that TIP1 binds the acyl group palmitate, that it can rescue the morphological, temperature sensitivity, and yeast casein kinase2 localization defects of the yeast S-acyl transferase mutant akr1 Delta, and that inhibition of acylation in wild-type Arabidopsis roots reproduces the Tip1(-) mutant phenotype. Our results demonstrate that S-acylation is essential for normal plant cell growth and identify a plant S-acyl transferase, an essential research tool if we are to understand how this important, reversible lipid modification operates in plant cells.