Discovery of diversity in xylan biosynthetic genes by transcriptional profiling of a heteroxylan containing mucilaginous tissue.
Discovery of diversity in xylan biosynthetic genes by transcriptional profiling of a heteroxylan containing mucilaginous tissue.
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通过含有粘液组织的异木聚糖的转录谱发现木聚糖生物合成基因的多样性。
DOI：
10.3389/fpls.2013.00183
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发表时间：
2013
影响因子：
5.6
通讯作者：
Wilkerson CG
中科院分区：
文献类型：
--
作者：
Jensen JK;Johnson N;Wilkerson CG
木聚糖骨架合成的确切生物化学步骤仍然难以捉摸。在拟南芥中，来自两个糖基转移酶（GT）家族的三个非冗余基因，即来自GT 43的IRX 9和IRX 14以及来自GT 47的IRX 10，是形成木聚糖骨架的候选基因。在其他植物中，有证据表明，不同的组织表达这三个基因在很大程度上不同的水平，这表明，在木聚糖合成酶复合物的组成的多样性存在。最近，我们已经分析了转录本在发育中的粘液组织的车前（车前草ovata Forsk）。发现该组织具有高水平的IRX 10同源物表达，但两个GT 43家族成员的表达水平非常低。这与最近发现相对高丰度的GT 43家族成员的小麦胚乳组织分析形成对比。我们已经进行了深入的分析，所有GT基因表达在四个发展阶段的车前粘液层和一个阶段的车前干使用RNA-Seq。该分析揭示了几种IRX 10同源物，GT 61中的扩增（At 3g 18170/At 3g 18180的同源物），以及来自其他GT家族的几种GT，其在粘液组织中高度丰富并特异性表达。我们目前的假设是，存在于粘液组织中的四个IRX 10基因已经进化到在没有GT 43基因的情况下发挥功能。这四个基因代表了迄今为止发现的最具分歧的IRX 10基因。相反，存在于车前茎中的那些与其他真双子叶植物中的那些非常相似。这表明这些基因处于选择压力下，可能是由于粘液中存在的各种木聚糖结构的合成，其具有与次生壁中存在的不同的生化作用。众多的GT 61家族成员也显示出广泛的序列多样性，并且可能是车前子粘液中存在的大量侧链结构的原因。
The exact biochemical steps of xylan backbone synthesis remain elusive. In Arabidopsis, three non-redundant genes from two glycosyltransferase (GT) families, IRX9 and IRX14 from GT43 and IRX10 from GT47, are candidates for forming the xylan backbone. In other plants, evidence exists that different tissues express these three genes at widely different levels, which suggests that diversity in the makeup of the xylan synthase complex exists. Recently we have profiled the transcripts present in the developing mucilaginous tissue of psyllium (Plantago ovata Forsk). This tissue was found to have high expression levels of an IRX10 homolog, but very low levels of the two GT43 family members. This contrasts with recent wheat endosperm tissue profiling that found a relatively high abundance of the GT43 family members. We have performed an in-depth analysis of all GTs genes expressed in four developmental stages of the psyllium mucilagenous layer and in a single stage of the psyllium stem using RNA-Seq. This analysis revealed several IRX10 homologs, an expansion in GT61 (homologs of At3g18170/At3g18180), and several GTs from other GT families that are highly abundant and specifically expressed in the mucilaginous tissue. Our current hypothesis is that the four IRX10 genes present in the mucilagenous tissues have evolved to function without the GT43 genes. These four genes represent some of the most divergent IRX10 genes identified to date. Conversely, those present in the psyllium stem are very similar to those in other eudicots. This suggests these genes are under selective pressure, likely due to the synthesis of the various xylan structures present in mucilage that has a different biochemical role than that present in secondary walls. The numerous GT61 family members also show a wide sequence diversity and may be responsible for the larger number of side chain structures present in the psyllium mucilage.
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DOI：
10.1073/pnas.0706569104
发表时间：
2007-09-25
影响因子：
11.1
作者：
Desprez, Thierry;Juraniec, Michal;Vernhettes, Samantha
通讯作者：
Vernhettes, Samantha
DOI：
10.1073/pnas.1202079109
发表时间：
2012-10-16
影响因子：
11.1
作者：
Chiniquy, Dawn;Sharma, Vaishali;Ronald, Pamela C.
通讯作者：
Ronald, Pamela C.
影响因子：
7.4
作者：
Bischoff, Volker;Nita, Silvia;Scheible, Wolf-Ruediger
通讯作者：
Scheible, Wolf-Ruediger
影响因子：
11.6
作者：
Burget, EG;Verma, R;Reiter, WD
通讯作者：
Reiter, WD
影响因子：
3.1
作者：
Fischer, MH;Yu, NX;Marlett, JA
通讯作者：
Marlett, JA