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Title: Divergent expression of cytokinin biosynthesis, signaling and catabolism genes underlying differences in feeding sites induced by cyst and root‐knot nematodes
Summary

Cyst and root‐knot nematodes are obligate parasites of economic importance with a remarkable ability to reprogram root cells into unique metabolically active feeding sites. Previous studies have suggested a role for cytokinin in feeding site formation induced by these two types of nematodes, but the mechanistic details have not yet been described. Using Arabidopsis as a host plant species, we conducted a comparative analysis of cytokinin genes in response to the beet cyst nematode (BCN),Heterodera schachtii, and the root‐knot nematode (RKN),Meloidogyne incognita. We identified distinct differences in the expression of cytokinin biosynthesis, catabolism and signaling genes in response to infection byBCNandRKN, suggesting differential manipulation of the cytokinin pathway by these two nematode species. Furthermore, we evaluated Arabidopsis histidine kinase receptor mutant linesahk2/3,ahk2/4andahk3/4in response toRKNinfection. Similar to our previous studies withBCN, these lines were significantly less susceptible toRKNwithout compromising nematode penetration, suggesting a requirement of cytokinin signaling inRKNfeeding site formation. Moreover, an analysis ofahkdouble mutants usingCycB1;1:GUS/ahkintrogressed lines revealed contrasting differences in the cytokinin receptors mediating cell cycle activation in feeding sites induced byBCNandRKN.

 
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NSF-PAR ID:
10039869
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
The Plant Journal
Volume:
92
Issue:
2
ISSN:
0960-7412
Page Range / eLocation ID:
p. 211-228
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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