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Title: Lateral Leaflet Suppression 1 ( LLS1 ), encoding the MtYUCCA1 protein, regulates lateral leaflet development in Medicago truncatula
Summary

In species with compound leaves, the positions of leaflet primordium initiation are associated with local peaks of auxin accumulation. However, the role of auxin during the late developmental stages and outgrowth of compound leaves remains largely unknown.

Using genome resequencing approaches, we identified insertion sites at four alleles of theLATERAL LEAFLET SUPPRESSION1(LLS1) gene, encoding the auxin biosynthetic enzyme YUCCA1 inMedicago truncatula.

Linkage analysis and complementation tests showed that thells1mutant phenotypes were caused by theTnt1insertions that disrupted theLLS1gene. The transcripts ofLLS1can be detected in primordia at early stages of leaf initiation and later in the basal regions of leaflets, and finally in vein tissues at late leaf developmental stages. Vein numbers and auxin content are reduced in thells1‐1mutant. Analysis of thells1 sgl1andlls1 palm1double mutants revealed thatSGL1is epistatic toLLS1, andLLS1works withPALM1in an independent pathway to regulate the growth of lateral leaflets.

Our work demonstrates that the YUCCA1/YUCCA4 subgroup plays very important roles in the outgrowth of lateral leaflets during compound leaf development ofM. truncatula, in addition to leaf venation.

 
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NSF-PAR ID:
10401917
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
New Phytologist
Volume:
227
Issue:
2
ISSN:
0028-646X
Page Range / eLocation ID:
p. 613-628
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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