Analysis of early processes in wound-induced vascular regeneration using TED3 and ZeHB3 as molecular markers.
Analysis of early processes in wound-induced vascular regeneration using TED3 and ZeHB3 as molecular markers.
复制标题
使用 TED3 和 ZeHB3 作为分子标记分析伤口诱导的血管再生的早期过程。
DOI：
10.1093/pcp/pcf008
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发表时间：
2002
影响因子：
4.9
通讯作者：
H. Fukuda
中科院分区：
文献类型：
--
作者：
C. Nishitani;T. Demura;H. Fukuda
在伤后4d内，中断百日菊节间维管束诱导细胞转分化为管分子（TEs）或筛分子（SEs）。再生过程的早期阶段进行了分析，使用两个分子标记基因，TED 3和ZeHB 3，这两个基因分别在TE前体细胞和未成熟韧皮部细胞中特异性表达。表达TED 3和ZeHB 3 mRNA的细胞数量的增加总是先于形成的TE和SE数量的增加。维管分化的最早迹象是在沿着沿着切断的维管束的束间和束内形成层样区域中受伤后24小时出现TED 3 mRNA表达细胞层。与此相反，ZeHB 3 mRNA表达细胞的数量显着下降沿着切断束后24小时，并在36小时后再次增加。这些结果清楚地表明，木质部和韧皮部分化在维管再生过程中是不同步的。用10（-3）M秋水仙素处理废除髓实质中ZeHB 3 mRNA的表达，但不废除TED 3 mRNA;这表明细胞分裂是髓实质细胞转分化为表达ZeHB 3的未成熟韧皮部细胞的先决条件。相反，髓实质细胞向TE前体细胞的转分化不需要预先的细胞分裂。然而，细胞分裂的抑制阻止了TEs的径向文件和TED 3 mRNA表达细胞的形成层样层的形成，并最终阻止了血管再生。这些结果表明，伤口诱导的形成层样活性和切断的维管束之间是必不可少的血管再生。
Interruption of the vascular bundles of Zinnia internodes induced transdifferentiation of cells into tracheary elements (TEs) or sieve elements (SEs) within 4 d of wounding. The early stage of the regeneration processes was analyzed using two molecular marker genes, TED3 and ZeHB3, which are expressed specifically in TE precursor cells and immature phloem cells, respectively. An increase in the numbers of TED3 and ZeHB3 mRNA-expressing cells always preceded an increase in the numbers of TEs and SEs formed. The earliest sign of vascular differentiation was the appearance 24 h after wounding of a layer(s) of TED3 mRNA-expressing cells in the inter- and intrafascicular cambial-like regions along the severed vascular bundles. In contrast, the number of ZeHB3 mRNA-expressing cells decreased dramatically along the severed bundles 24 h after wounding, and increased again 36 h after wounding. These results clearly indicate that xylem and phloem differentiation are not synchronized during vascular regeneration. Treatment with 10(-3) M colchicine abolished the expression of ZeHB3 mRNA in pith parenchyma, but not TED3 mRNA; this suggests that cell division is a prerequisite for the transdifferentiation of pith parenchymal cells into immature phloem cells expressing ZeHB3. In contrast, transdifferentiation of pith parenchymal cells to TE precursor cells does not require preceding cell division. However, the inhibition of cell division prevented the formation of both radial files of TEs and the cambial-like layer(s) of TED3 mRNA-expressing cells, and, ultimately, vascular regeneration altogether. These results imply that wound-induced cambial-like activity in and between severed vascular bundles is essential for vascular regeneration.