CNRS, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, Roscoff, France; Sorbonne Universités, UPMC Univ Paris 06, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, Roscoff, France.
Muroran Marine Station, Field Science Center for Northern Biosphere, Hokkaido University, Muroran 051-0013, Japan.
Semin Cell Dev Biol. 2023 Jan 30;134:112-124. doi: 10.1016/j.semcdb.2022.03.005. Epub 2022 Mar 17.
In brown algae, the extracellular matrix (ECM) and its constitutive polymers play crucial roles in specialized functions, including algal growth and development. In this review we offer an integrative view of ECM construction in brown algae. We briefly report the chemical composition of its main constituents, and how these are interlinked in a structural model. We examine the ECM assembly at the tissue and cell level, with consideration on its structure in vivo and on the putative subcellular sites for the synthesis of its main constituents. We further discuss the biosynthetic pathways of two major polysaccharides, alginates and sulfated fucans, and the progress made beyond the candidate genes with the biochemical validation of encoded proteins. Key enzymes involved in the elongation of the glycan chains are still unknown and predictions have been made at the gene level. Here, we offer a re-examination of some glycosyltransferases and sulfotransferases from published genomes. Overall, our analysis suggests novel investigations to be performed at both the cellular and biochemical levels. First, to depict the location of polysaccharide structures in tissues. Secondly, to identify putative actors in the ECM synthesis to be functionally studied in the future.
在褐藻中，细胞外基质（ECM）及其组成聚合物在特殊功能中起着至关重要的作用，包括藻类的生长和发育。在这篇综述中，我们提供了对褐藻 ECM 构建的综合观点。我们简要报告了其主要成分的化学组成，以及这些成分如何在结构模型中相互关联。我们检查了组织和细胞水平上的 ECM 组装，考虑了其在体内的结构以及其主要成分合成的假定亚细胞部位。我们进一步讨论了两种主要多糖（褐藻酸盐和硫酸化岩藻聚糖）的生物合成途径，以及在生化验证编码蛋白的基础上，对候选基因的研究进展。参与聚糖链伸长的关键酶仍然未知，并且已经在基因水平上进行了预测。在这里，我们对来自已发表基因组的一些糖基转移酶和硫酸转移酶进行了重新检查。总的来说，我们的分析表明需要在细胞和生化水平上进行新的研究。首先，要描绘多糖结构在组织中的位置。其次，要确定 ECM 合成中的假定因子，以便在未来进行功能研究。
