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Title: The peptide GOLVEN10 alters root development and noduletaxis in Medicago truncatula
SUMMARY The conservation of GOLVEN (GLV)/ROOT MERISTEM GROWTH FACTOR (RGF) peptide encoding genes across plant genomes capable of forming roots or root‐like structures underscores their potential significance in the terrestrial adaptation of plants. This study investigates the function and role of GOLVEN peptide‐coding genes inMedicago truncatula. Five out of fifteen GLV/RGF genes were notably upregulated during nodule organogenesis and were differentially responsive to nitrogen deficiency and auxin treatment. Specifically, the expression ofMtGLV9andMtGLV10at nodule initiation sites was contingent upon the NODULE INCEPTION transcription factor. Overexpression of these five nodule‐induced GLV genes in hairy roots ofM. truncatulaand application of their synthetic peptide analogues led to a decrease in nodule count by 25–50%. Uniquely, the GOLVEN10 peptide altered the positioning of the first formed lateral root and nodule on the primary root axis, an observation we term ‘noduletaxis’; this decreased the length of the lateral organ formation zone on roots. Histological section of roots treated with synthetic GOLVEN10 peptide revealed an increased cell number within the root cortical cell layers without a corresponding increase in cell length, leading to an elongation of the root likely introducing a spatiotemporal delay in organ formation. At the transcription level, the GOLVEN10 peptide suppressed expression of microtubule‐related genes and exerted its effects by changing expression of a large subset of Auxin responsive genes. These findings advance our understanding of the molecular mechanisms by which GOLVEN peptides modulate root morphology, nodule ontogeny, and interactions with key transcriptional pathways.  more » « less
Award ID(s):
2217830
PAR ID:
10541087
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
The Plant Journal
Volume:
118
Issue:
3
ISSN:
0960-7412
Page Range / eLocation ID:
607 to 625
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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