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Title: Comparative transcriptomic analysis of apple and peach fruits: insights into fruit type specification
SUMMARY

Fruits represent key evolutionary innovations in angiosperms and exhibit diverse types adapted for seed dissemination. However, the mechanisms that underlie fruit type diversity are not understood. The Rosaceae family comprises many different fruit types, including ‘pome’ and ‘drupe’ fruits, and hence is an excellent family for investigating the genetic basis of fruit type specification. Using comparative transcriptomics, we investigated the molecular events that correlate with pome (apple) and drupe (peach) fleshy fruit development, focusing on the earliest stages of fruit initiation. We identifiedPIandTM6, MADS box genes whose expression negatively correlates with fruit flesh‐forming tissues irrespective of fruit type. In addition, the MADS box geneFBP9is expressed in fruit‐forming tissues in both species, and was lost multiple times in the genomes of dry‐fruit‐forming eudicots including Arabidopsis. Network analysis reveals co‐expression betweenFBP9and photosynthesis genes in both apple and peach, suggesting thatFBP9and photosynthesis may both promote fleshy fruit development. The large transcriptomic datasets at the earliest stages of pome and drupe fruit development provide rich resources for comparative studies, and the work provides important insights into fruit‐type specification.

 
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NSF-PAR ID:
10445265
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
The Plant Journal
Volume:
109
Issue:
6
ISSN:
0960-7412
Page Range / eLocation ID:
p. 1614-1629
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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