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Title: Temporal and spatial transcriptomic and micro RNA dynamics of CAM photosynthesis in pineapple
Summary

The altered carbon assimilation pathway of crassulacean acid metabolism (CAM) photosynthesis results in an up to 80% higher water‐use efficiency than C3photosynthesis in plants making it a potentially useful pathway for engineering crop plants with improved drought tolerance. Here we surveyed detailed temporal (diel time course) and spatial (across a leaf gradient) gene and microRNA(miRNA) expression patterns in the obligateCAMplant pineapple [Ananas comosus(L.) Merr.]. The high‐resolution transcriptome atlas allowed us to distinguish betweenCAM‐related and non‐CAMgene copies. A differential gene co‐expression network across green and white leaf diel datasets identified genes with circadian oscillation,CAM‐related functions, and source‐sink relations. Gene co‐expression clusters containingCAMpathway genes are enriched with clock‐associatedcis‐elements, suggesting circadian regulation ofCAM. About 20% of pineapple microRNAs have diel expression patterns, with several that target keyCAM‐related genes. Expression and physiology data provide a model forCAM‐specific carbohydrate flux and long‐distance hexose transport. Together these resources provide a list of candidate genes for targeted engineering ofCAMinto C3photosynthesis crop species.

 
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PAR ID:
10038640
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
The Plant Journal
Volume:
92
Issue:
1
ISSN:
0960-7412
Page Range / eLocation ID:
p. 19-30
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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