Srivastava Moumita, Sadanandom Ari
Department of Biosciences, Durham University, Stockton Road, Durham DH1 3LE, UK.
Plants (Basel). 2020 Dec 17;9(12):1788. doi: 10.3390/plants9121788.
Due to their sessile nature, plants are constantly subjected to various environmental stresses such as drought, salinity, and pathogen infections. Post-translational modifications (PTMs), like SUMOylation, play a vital role in the regulation of plant responses to their environment. The process of SUMOylation typically involves an enzymatic cascade containing the activation, (E1), conjugation (E2), and ligation (E3) of SUMO to a target protein. Additionally, it also requires a class of SUMO proteases that generate mature SUMO from its precursor and cleave it off the target protein, a process termed deSUMOylation. It is now clear that SUMOylation in plants is key to a plethora of adaptive responses. How this is achieved with an extremely limited set of machinery components is still unclear. One possibility is that novel SUMO components are yet to be discovered. However, current knowledge indicates that only a small set of enzymes seem to be responsible for the modification of a large number of SUMO substrates. It is yet unknown where the specificity lies within the SUMO system. Although this seems to be a crucial question in the field of SUMOylation studies, not much is known about the factors that provide specificity. In this review, we highlight the role of the localisation of SUMO components as an important factor that can play a vital role in contributing to the specificity within the process. This will introduce a new facet to our understanding of the mechanisms underlying such a dynamic process.
由于植物固着生长的特性，它们经常受到各种环境胁迫，如干旱、盐害和病原体感染。翻译后修饰（PTM），如SUMO化，在调节植物对环境的反应中起着至关重要的作用。SUMO化过程通常涉及一个酶促级联反应，包括SUMO对靶蛋白的激活（E1）、缀合（E2）和连接（E3）。此外，它还需要一类SUMO蛋白酶，这类酶能从前体生成成熟的SUMO，并将其从靶蛋白上切割下来，这一过程称为去SUMO化。现在很清楚，植物中的SUMO化是众多适应性反应的关键。然而，如何用一套极其有限的机制组件来实现这一点仍不清楚。一种可能性是尚未发现新的SUMO组件。然而，目前的知识表明，似乎只有一小部分酶负责修饰大量的SUMO底物。SUMO系统的特异性究竟在哪里尚不清楚。尽管这似乎是SUMO化研究领域的一个关键问题，但对于提供特异性的因素知之甚少。在这篇综述中，我们强调SUMO组件定位的作用，它是一个重要因素，在该过程的特异性形成中可能起着至关重要的作用。这将为我们理解这一动态过程背后的机制引入一个新的方面。
