Plant oxidosqualene metabolism: cycloartenol synthase-dependent sterol biosynthesis in Nicotiana benthamiana.
Plant oxidosqualene metabolism: cycloartenol synthase-dependent sterol biosynthesis in Nicotiana benthamiana.
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DOI：
10.1371/journal.pone.0109156
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发表时间：
2014
期刊：
影响因子：
3.7
通讯作者：
Schaller H
中科院分区：
文献类型：
--
作者：
Gas-Pascual E;Berna A;Bach TJ;Schaller H
与后生动物相比，植物甾醇途径表现出主要的生物合成差异。甾醇的前体是五环环artenol (9β,19- cycloolanost -24-en-3 - β-ol)，而不是羊毛甾醇（羊毛甾醇-8,24-dien-3 - β-ol），正如60年代后期所显示的那样。然而，过去几年的植物基因组挖掘揭示了氧化角鲨烯环化酶库中普遍存在羊毛甾醇合成酶编码序列（LAS1），以及环artenol合成酶（CAS1）和非甾体三萜合成酶，这些酶有助于地球上C30H50O化合物的代谢多样性。此外，植物LAS1蛋白已经通过肽特征和它们补充酵母羊毛甾醇合成酶缺陷的能力得到了明确的鉴定。据报道，在拟南芥模型中，通过羊毛甾醇和环artenol合成甾醇的双重途径，尽管羊毛甾醇途径对24-烷基-Δ5-sterols产生的贡献相当小（Ohyama et al. (2009) PNAS 106, 725）。为了进一步研究CAS1和LAS1基因在植物中的生理相关性，我们在烟叶中沉默了它们的表达。我们使用基于烟草CAS1基因特异性序列或来自solgenomics initiative （http://solgenomics.net/）的病毒诱导基因沉默（VIGS）来挑战CAS1和LAS1各自的作用。在本报告中，我们在工程酵母中发现了CAS1特异性的功能性甾醇途径，以及烟草甾醇生物合成严格依赖CAS1的途径。
The plant sterol pathway exhibits a major biosynthetic difference as compared with that of metazoans. The committed sterol precursor is the pentacyclic cycloartenol (9β,19-cyclolanost-24-en-3β-ol) and not lanosterol (lanosta-8,24-dien-3β-ol), as it was shown in the late sixties. However, plant genome mining over the last years revealed the general presence of lanosterol synthases encoding sequences (LAS1) in the oxidosqualene cyclase repertoire, in addition to cycloartenol synthases (CAS1) and to non-steroidal triterpene synthases that contribute to the metabolic diversity of C30H50O compounds on earth. Furthermore, plant LAS1 proteins have been unambiguously identified by peptidic signatures and by their capacity to complement the yeast lanosterol synthase deficiency. A dual pathway for the synthesis of sterols through lanosterol and cycloartenol was reported in the model Arabidopsis thaliana, though the contribution of a lanosterol pathway to the production of 24-alkyl-Δ5-sterols was quite marginal (Ohyama et al. (2009) PNAS 106, 725). To investigate further the physiological relevance of CAS1 and LAS1 genes in plants, we have silenced their expression in Nicotiana benthamiana. We used virus induced gene silencing (VIGS) based on gene specific sequences from a Nicotiana tabacum CAS1 or derived from the solgenomics initiative (http://solgenomics.net/) to challenge the respective roles of CAS1 and LAS1. In this report, we show a CAS1-specific functional sterol pathway in engineered yeast, and a strict dependence on CAS1 of tobacco sterol biosynthesis.
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影响因子：
2.3
作者：
Guhling, O;Kinzler, C;Jetter, R
通讯作者：
Jetter, R
影响因子：
62.1
作者：
Nes, W. David
通讯作者：
Nes, W. David
DOI：
10.1073/pnas.90.24.11628
发表时间：
1993-12-15
影响因子：
11.1
作者：
COREY, EJ;MATSUDA, SPT;BARTEL, B
通讯作者：
BARTEL, B
影响因子：
7.2
作者：
BAULCOMBE, DC;CHAPMAN, S;CRUZ, SS
通讯作者：
CRUZ, SS
影响因子：
4.8
作者：
Lovato, MA;Hart, EA;Matsuda, SPT
通讯作者：
Matsuda, SPT