Kemat Nurashikin, Visser Richard G F, Krens Frans A
Plant Breeding, Wageningen University and Research, P.O. Box 386, 6700 AJ Wageningen, The Netherlands.
Department of Agriculture Technology, Faculty of Agriculture, Universiti Putra Malaysia, Serdang 43400, Malaysia.
Plants (Basel). 2021 Nov 29;10(12):2625. doi: 10.3390/plants10122625.
One of the characteristics of hyperhydric plants is the reduction of cell wall lignification (hypolignification), but how this is related to the observed abnormalities of hyperhydricity (HH), is still unclear. Lignin is hydrophobic, and we speculate that a reduction in lignin levels leads to more capillary action of the cell wall and consequently to more water in the apoplast. -coumaric acid is the hydroxyl derivative of cinnamic acid and a precursor for lignin and flavonoids in higher plant. In the present study, we examined the role of lignin in the development of HH in by checking the wild-types (Ler and Col-0) and mutants affected in phenylpropanoid biosynthesis, in the gene coding for cinnamate 4-hydroxylase, C4H ( and ). Exogenously applied -coumaric acid decreased the symptoms of HH in both wild-type and less-lignin mutants. Moreover, the results revealed that exogenously applied -coumaric acid inhibited root growth and increased the total lignin content in both wild-type and less-lignin mutants. These effects appeared to diminish the symptoms of HH and suggest an important role for lignin in HH.
玻璃化苗的特征之一是细胞壁木质化程度降低（木质化不足），但这与观察到的玻璃化异常（HH）之间的关系仍不清楚。木质素具有疏水性，我们推测木质素水平的降低会导致细胞壁产生更多的毛细作用，从而使质外体中含有更多水分。对香豆酸是肉桂酸的羟基衍生物，是高等植物中木质素和类黄酮的前体。在本研究中，我们通过检测野生型（Ler和Col-0）以及在苯丙烷生物合成中、编码肉桂酸4-羟化酶（C4H）的基因（ 和 ）中受影响的突变体，研究了木质素在 中HH发育过程中的作用。外源施加对香豆酸可减轻野生型和木质素含量较低的突变体中的HH症状。此外，结果表明，外源施加对香豆酸会抑制野生型和木质素含量较低的突变体的根生长，并增加其总木质素含量。这些效应似乎减轻了HH症状，并表明木质素在HH中起重要作用。
