The beta-N-acetylhexosaminidase gene family in the brown planthopper, Nilaparvata lugens
The beta-N-acetylhexosaminidase gene family in the brown planthopper, Nilaparvata lugens
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褐飞虱 Nilaparvata lugens 中的 β-N-乙酰氨基己糖苷酶基因家族
DOI：
10.1111/imb.12187
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发表时间：
2015
影响因子：
2.6
通讯作者：
Zhang C. -X.
中科院分区：
文献类型：
--
作者：
Xi Y.;Pan P. -L.;Zhang C. -X.
β-N-乙酰己糖胺酶 (HEX) 是一种可以降解昆虫几丁质酶活性产生的几丁质寡糖的酶。使用基于基因组和转录组数据库的生物信息学方法，对褐飞虱中的 11 个 β-N-乙酰己糖胺酶基因 (NlHexs) 进行了鉴定和表征。系统发育分析揭示了六组树拓扑。 O-连接 N-乙酰氨基葡萄糖苷酶 (O-GlcNAcase) 组包括 NlHex11，其具有与其他 10NlHex 不同的催化结构域。对NlHexs在不同发育阶段表达的观察表明，NlHex4在换羽过程中呈周期性表达。尽管大多数 NlHexs 的组织特异性表达模式是非特异性的，但发现 NlHex4 主要在女性生殖系统以及体被中表达。 RNA干扰（RNAi）证明，只有用靶向NlHex4的双链RNA（dsRNA）处理的若虫无法脱落旧角质层，这些若虫最终死亡；在用靶向其他 10N1Hex 的 dsRNA 处理的昆虫中没有发现可观察到的形态异常。基于这项研究和我们之前的分析，提出了“5 + 1 + 3”的几丁质分解酶模式，其中N中的蜕皮需要5种几丁质酶、1种NlHEX和3种几丁质脱乙酰酶。 吕根斯。更好地了解半变态昆虫的几丁质代谢，N. 褐飞虱，将通过考虑三个几丁质分解酶家族来实现：几丁质酶、几丁质脱乙酰酶和β-N-乙酰己糖胺酶。
β‐N‐Acetylhexosaminidases (HEXs) are enzymes that can degrade the chitin oligosaccharides that are produced by the activity of chitinases on chitin in insects. Using bioinformatic methods based on genome and transcriptome databases, 11 β‐N‐acetylhexosaminidase genes (NlHexs) inNilaparvata lugenswere identified and characterized. Phylogenetic analysis revealed a six‐grouped tree topology. The O‐LinkedN‐acetylglucosaminidase (O‐GlcNAcase) group includesNlHex11, which harbours a catalytic domain that differs from that of the other 10NlHexs. Observations of the expression ofNlHexs during different developmental stages revealed thatNlHex4is expressed with periodicity during moulting. Although the tissue‐specific expression patterns of mostNlHexs were nonspecific,NlHex4was found to be expressed mainly in the female reproductive system as well as in the integument. RNA interference (RNAi) demonstrated failure to shed the old cuticle only in the nymphs treated with double‐stranded RNA (dsRNA) targetingNlHex4, and these nymphs eventually died; no observable morphological abnormalities were found in insects treated with dsRNAs targeting the other 10NlHexs. Based on this study and our previous analyses, a ‘5 + 1 + 3’ pattern of chitinolytic enzymes is proposed, in which five chitinases, one NlHEX and three chitin deacetylases are required for moulting inN. lugens. A better understanding of chitin metabolism in the hemimetabolous insect,N. lugens, would be achieved by considering three chitinolytic enzyme families: chitinase, chitin deacetylase and β‐N‐acetylhexosaminidase.