The Tubα3 gene from Zea mays : structure and expression in dividing plant tissues
The Tubα3 gene from Zea mays : structure and expression in dividing plant tissues
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来自玉米的 Tubα3 基因：分裂植物组织中的结构和表达
DOI：
10.1016/0378-1119(90)90388-8
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发表时间：
1990
期刊：
影响因子：
3.5
通讯作者：
J. Rigau
中科院分区：
文献类型：
--
作者：
L. Montoliu;P. Puigdomènech;J. Rigau
从玉米中克隆了一个编码α-Tub的基因（Tubα3），该基因在分裂组织中表达。推导的氨基酸序列长450个氨基酸，与已报道的其它植物α-Tub的氨基酸序列（85-89%）非常相似，特别是与已报道的同一物种的另外两个氨基酸序列（α1-Tub和α2-Tub）（93%）相似。Tub α 1和Tub α 2基因的基因组结构也非常相似，有三个内含子位于Tub α 1和Tub α 2基因的相同位置，其中一个内含子位于拟南芥同源基因的相同位置。然而，非编码序列与其他两个玉米基因组序列非常不同。特别是，在5′上游或3′非翻译序列中均未发现同源性。使用特异性3′探针，可以在许多测量的植物器官中检测到该基因编码的mRNA，但在富含分裂细胞的器官中观察到其最高丰度，这与组蛋白H4编码基因的模式相关。在玉米胚芽鞘中鉴定了一个cDNA克隆并测序，证实了Tub α 3在该器官中的表达。与已描述的Tub α 1和Tub α 2基因中观察到的相反，在植物的任何器官中均未发现优先积累。Tub α基因家族在玉米中似乎至少由两组同源序列组成，每组最多包括两个或三个编码单位。
A gene (Tubα3) coding for an α-Tub, expressed in dividing tissues, has been cloned fromZea mays. The deduced amino acid (aa) sequence, 450 aa long, is very similar to the other plant α-Tub (85–89% homology) so far reported, and in particular to the other two aa sequences (α1-Tub and α2-Tub) already published from the same species (93% homology). The genomic structure is also very similar, having three introns located at the same positions as in theTubα1andTubα2genes, one of them placed at the same position in the homologous genes fromArabidopsis thaliana. Nevertheless, the noncoding sequences are very different from the two other maize genomic sequences. In particular, no homology has been found either in the 5′ upstream or in the 3′-untranslated sequences. Using specific 3′ probes, it has been possible to detect the mRNA coded by this gene in many of the plant organs measured, but its highest abundance is observed in the organs rich in dividing cells, a pattern correlated with that of the histone H4-encoding gene. A cDNA clone has been identified in maize coleoptiles and sequenced, confirming the expression of theTubα3in this organ. No prefential accumulation in any organ of the plant was found, in contrast with what was observed in theTubα1andTubα2genes already described. TheTubαgene family seems to consist in maize by at least two groups of homologous sequences, each one including a maximum of two or three coding units.