Spatiotemporal regulation of the arbuscular mycorrhiza symbiosis establishment

司他内酯 生物 丛枝菌根 共生 球囊菌门 植物 根际 真菌 菌根 菌丝 截形苜蓿 拟南芥 基因 突变体 生物化学 遗传学 细菌
作者
Bruno Guillotin
出处
期刊:Le Centre pour la Communication Scientifique Directe - HAL - Diderot
摘要

The arbuscular mycorrhiza (AM), a symbiosis between fungi from the phylum Glomeromycota and nearly 80% of terrestrial plant species. It is characterized by a two-way exchange in which the fungus provides mineral nutrients to the plant in exchange for carbohydrates. However this feeding of the fungus during the symbiotic process represents a significant carbon cost for the plant. To maintain a mutualistic interaction the two symbiotic partners have to strictly control the extent of fungal development in the roots. This control is called autoregulation. Several proteins have been found to be important for the regulation of the different mycorrhizal steps: the stimulation of fungal growth in the rhizosphere by the strigolactones, the fungal entrance in the roots, the hyphal proliferation in the roots and the arbuscule formation. In this work we examine in more detail the role of two of these proteins known to be involved in the mycorrhization process, the transcriptional factors NSP1 and NSP2 (Nodulation Signaling Pathway). We first confirm in M. truncatula roots the direct implication of NSP1 in the regulation of two strigolactone biosynthesis genes, DWARF27 (D27) and MAX1, during the asymbiotic conditions. Then, we show that NSP1, unlike NSP2, is a factor that promotes the fungal entries in the root, presumably due to its activation of D27 and MAX1 resulting in a stimulation of strigolactone synthesis and presymbiotic fungal growth. Next, during the later stages of mycorrhization, we highlight that in the colonized tissues NSP1 is absent and the induction of both D27 and MAX1 is not anymore NSP1 dependent. NSP1 protein is then localized in cells which are not yet colonized but are close to a colonization zone. There, it controls negatively the hyphal propagation in the root and positively the formation of arbuscules. In contrast, NSP2 is present in the colonized tissue where it promotes hyphal propagation and arbuscule development, perhaps by interacting with other proteins. We also show that if NSP1 proteins are absent of the colonized tissues, NSP1 transcripts are present. Unexpectedly, we unveil that in those colonized cells, NSP1 mRNA can protect, by a micro RNA (miR171h) decoy action called target mimicry, NSP2 mRNA against miR171h-mediated degradation. This is the first demonstration that a coding RNA molecule can be a target mimic for a microRNA. In our context this finding reveals a positive regulation of NSP2 expression by NSP1 transcripts and brings to light an additional layer of complexity in the mycorrhizal dual role of these two transcription factors. Finally, in tomato, we highlight that SlNSP1 could be directly or indirectly regulated by the AUX/IAA protein, SlIAA27. As a link with auxin we presume that this AUX/IAA protein is a new component of the signaling pathway controlling AM fungal colonization in tomato, and we propose that it controls strigolactone biosynthesis via the regulation of SlNSP1. Overall our work provides new pieces of the mycorrhizal puzzle and shows how important it is to perform spatiotemporal investigations for a better understanding of highly integrated and complex biological processes.

科研通智能强力驱动
Strongly Powered by AbleSci AI
更新
PDF的下载单位、IP信息已删除 (2025-6-4)

科研通是完全免费的文献互助平台,具备全网最快的应助速度,最高的求助完成率。 对每一个文献求助,科研通都将尽心尽力,给求助人一个满意的交代。
实时播报
小杨完成签到,获得积分10
1秒前
风华正茂完成签到,获得积分10
2秒前
康康完成签到 ,获得积分10
4秒前
柒z完成签到,获得积分10
6秒前
赘婿应助momo采纳,获得10
10秒前
油点小鳄完成签到,获得积分20
13秒前
14秒前
14秒前
桐桐应助wish采纳,获得10
15秒前
16秒前
桐桐应助百十余采纳,获得10
19秒前
义气如萱发布了新的文献求助10
19秒前
19秒前
20秒前
小二郎应助KM比比采纳,获得10
21秒前
不能吃了发布了新的文献求助10
21秒前
李健的粉丝团团长应助LJJ采纳,获得10
22秒前
23秒前
24秒前
体贴绝音发布了新的文献求助10
24秒前
25秒前
丘比特应助sakegeda采纳,获得10
27秒前
28秒前
wish发布了新的文献求助10
28秒前
不能吃了完成签到,获得积分10
29秒前
29秒前
30秒前
32秒前
好滴捏发布了新的文献求助10
34秒前
34秒前
pyt完成签到,获得积分10
35秒前
36秒前
英俊的铭应助不安的紫翠采纳,获得10
37秒前
38秒前
情怀应助SherlockHe采纳,获得10
38秒前
38秒前
40秒前
LJJ发布了新的文献求助10
41秒前
百十余发布了新的文献求助10
42秒前
44秒前
高分求助中
A new approach to the extrapolation of accelerated life test data 1000
ACSM’s Guidelines for Exercise Testing and Prescription, 12th edition 500
‘Unruly’ Children: Historical Fieldnotes and Learning Morality in a Taiwan Village (New Departures in Anthropology) 400
Indomethacinのヒトにおける経皮吸収 400
Phylogenetic study of the order Polydesmida (Myriapoda: Diplopoda) 370
基于可调谐半导体激光吸收光谱技术泄漏气体检测系统的研究 350
Robot-supported joining of reinforcement textiles with one-sided sewing heads 320
热门求助领域 (近24小时)
化学 材料科学 医学 生物 工程类 有机化学 生物化学 物理 内科学 纳米技术 计算机科学 化学工程 复合材料 遗传学 基因 物理化学 催化作用 冶金 细胞生物学 免疫学
热门帖子
关注 科研通微信公众号,转发送积分 3989334
求助须知:如何正确求助?哪些是违规求助? 3531428
关于积分的说明 11253936
捐赠科研通 3270119
什么是DOI,文献DOI怎么找? 1804887
邀请新用户注册赠送积分活动 882087
科研通“疑难数据库(出版商)”最低求助积分说明 809173