Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha, 410205, China.
Hunan Institute of Plant Protection, Changsha, 410205, China.
BMC Genomics. 2021 Dec 2;22(1):865. doi: 10.1186/s12864-021-08195-9.
Ramie is an important fiber-producing crop in China, and its fibers are widely used as textile materials. Fibers contain specialized secondary cellular walls that are mainly composed of cellulose, hemicelluloses, and lignin. Understanding the mechanism underlying the secondary wall biosynthesis of fibers will benefit the improvement of fiber yield and quality in ramie.
Here, we performed a proteomic analysis of the bark from the top and middle parts of the stem, where fiber growth is at different stages. We identified 6971 non-redundant proteins from bast bark. Proteomic comparison revealed 983 proteins with differential expression between the two bark types. Of these 983 proteins, 46 were identified as the homolog of known secondary wall biosynthetic proteins of Arabidopsis, indicating that they were potentially associated with fiber growth. Then, we proposed a molecular model for the secondary wall biosynthesis of ramie fiber. Furthermore, interaction analysis of 46 candidate proteins revealed two interacting networks that consisted of eight cellulose biosynthetic enzymes and seven lignin biosynthetic proteins, respectively.
This study sheds light on the proteomic basis underlying bast fiber growth in ramie, and the identification of many candidates associated with fiber growth provides important basis for understanding the fiber growth in this crop.
苎麻是中国重要的纤维作物，其纤维广泛用作纺织材料。纤维含有专门的次生细胞壁，主要由纤维素、半纤维素和木质素组成。了解纤维次生壁生物合成的机制将有助于提高苎麻的纤维产量和质量。
本研究对茎顶部和中部的韧皮部进行了蛋白质组学分析，这两个部位的纤维处于不同的生长阶段。我们从韧皮部中鉴定出了 6971 种非冗余蛋白。蛋白质组比较揭示了两种韧皮部之间有 983 种差异表达蛋白。其中 46 种被鉴定为拟南芥已知次生壁生物合成蛋白的同源物，表明它们可能与纤维生长有关。然后，我们提出了一个苎麻纤维次生壁生物合成的分子模型。此外，46 个候选蛋白的相互作用分析揭示了两个相互作用网络，分别由 8 种纤维素生物合成酶和 7 种木质素生物合成蛋白组成。
本研究揭示了苎麻韧皮纤维生长的蛋白质组基础，鉴定出的许多与纤维生长相关的候选蛋白为理解该作物的纤维生长提供了重要基础。
