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Title: The role of microRNAs in the legume–Rhizobium nitrogen-fixing symbiosis
Abstract Under nitrogen starvation, most legume plants form a nitrogen-fixing symbiosis with Rhizobium bacteria. The bacteria induce the formation of a novel organ called the nodule in which rhizobia reside as intracellular symbionts and convert atmospheric nitrogen into ammonia. During this symbiosis, miRNAs are essential for coordinating the various plant processes required for nodule formation and function. miRNAs are non-coding, endogenous RNA molecules, typically 20–24 nucleotides long, that negatively regulate the expression of their target mRNAs. Some miRNAs can move systemically within plant tissues through the vascular system, which mediates, for example, communication between the stem/leaf tissues and the roots. In this review, we summarize the growing number of miRNAs that function during legume nodulation focusing on two model legumes, Lotus japonicus and Medicago truncatula, and two important legume crops, soybean (Glycine max) and common bean (Phaseolus vulgaris). This regulation impacts a variety of physiological processes including hormone signaling and spatial regulation of gene expression. The role of mobile miRNAs in regulating legume nodule number is also highlighted.
Authors:
; ; ;
Award ID(s):
1734145
Publication Date:
NSF-PAR ID:
10156107
Journal Name:
Journal of Experimental Botany
Volume:
71
Issue:
5
Page Range or eLocation-ID:
1668 to 1680
ISSN:
0022-0957
Sponsoring Org:
National Science Foundation
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