2018年12月24日 · Here, we identified an Aux/INDOLE-3-ACETIC ACID 9 (IAA9)-AUXIN RESPONSE FACTOR 5 (ARF5) module in Populus tomentosa as a key mediator of auxin signaling to control early developing xylem development. PtoIAA9, a canonical Aux / IAA gene, is predominantly expressed in vascular cambium and developing secondary xylem and induced by exogenous auxin.

2019年3月3日 · ARF5 activated by auxin then promotes HB8 transcription and HB8 in turn activates PIN1 expression. This positive feedback regulation supporting canalization model enables the formation of vascular strands along the auxin flow (Baima et al., 1995, 2001; Scarpella et al., 2006).

Here, we identified an Aux/INDOLE-3-ACETIC ACID 9 (IAA9)-AUXIN RESPONSE FACTOR 5 (ARF5) module in Populus tomentosa as a key mediator of auxin signaling to control early developing xylem development. PtoIAA9, a canonical Aux/IAA gene, is predominantly expressed in vascular cambium and developing secondary xylem and induced by exogenous auxin.

ARF5 (auxin response factor) protein limits the number of stem cells through the weakening of WOX4 activity and increases the expression of the HB8 gene, positively affecting xylem differentiation ...

2018年12月27日 · We identify the auxin-dependent transcription factor ARF5/MONOPTEROS to cell-autonomously restrict the number of stem cells by directly attenuating the activity of the stem cell-promoting WOX4 gene. In contrast, ARF3 and ARF4 function as cambium activators in a redundant fashion from outside of WOX4-expressing cells.

2018年12月26日 · 生化实验显示，ARF5 可以直接结合在 HB7/ HB8 的启动子上，并激活其表达，进而启动维管形成层细胞向次生木质部的分化，促进木材形成。

研究发现:HD-ZIP III基因家族中的HB7、HB8 在过表达IAA9 株系中受到明显抑制,IAA9-ARF5 模块共同调控HB7、HB8对生长素的响应,促进木质部分化[30] ,还发现ARF7 通过下游的WOX4提高形成层干细胞活性,促进形成层向次生木质部的分化[10]。

ARF5 (auxin response factor) protein limits the number of stem cells through the weakening of WOX4 activity and increases the expression of the HB8 gene, positively affecting xylem differentiation ...

2021年2月23日 · Several ARFs such as ARF5/MONOPTEROS modulate cambium development. In the stem, ARF5 stimulates the transition of cambial stem cells into xylem cells by directly activating xylem-related genes and by repressing the key cambial regulator WOX4, whereas ARF3 and ARF4 maintain cambial stem cell proliferation (Brackmann et al., 2018).

ARF5（生长素响应因子5）则能够直接激活两个HD－ZIP III（同源结构域拉链）转录因子基因的表达，启动维管形成层细胞向次生木质部的分化，从而促进木材形成。