Early wound-responsive cues regulate the expression of WRKY family genes in chickpea differently under wounded and unwounded conditions.

Insect wounding activates a large number of signals that function coordinately to modulate gene expression and elicit defense responses. How each signal influences gene expression in absence of wounding is also important since it can shed light on changes occurring during the shift to wound response. Using simulated Helicoverpa armigera herbivory on chickpea, we had identified at least 14 WRKY genes that showed 5-50 fold increase in expression within 5-20 min of wounding. Our studies show that contrary to their collective effects upon wounding, individual chemical cues show distinct and often opposite effects in absence of wounding. In particular, jasmonic acid, a key early defense hormone, reduced transcripts of most WRKY genes by > 50% upon treatment of unwounded chickpea leaves as did salicylic acid. Neomycin (a JA biosynthesis inhibitor) delayed and also reduced early wound expression. H2O2 transiently activated several genes within 5-20 min by 5-8 fold while ethylene activated only a few WRKY genes by 2-5 fold. The summation of the individual effects of these chemical cues does not explain the strong increase in transcript levels upon wounding. Detailed studies of a 931 nt region of the CaWRKY41 promoter, show strong wound-responsive GUS expression in Arabidopsis even in presence of neomycin. Surprisingly its expression was lost in the coi1, ein2 and myc2myc3myc4 mutant backgrounds suggesting the requirement of intact ethylene and JA signaling pathways (dependent on MYCs) for wound-responsive expression. The studies highlight the complexity of gene regulation by different chemical cues in the presence and absence of wounding. Supplementary Information: The online version contains Supplementary material available at 10.1007/s12298-022-01170-y.

rs4246215 is targeted by hsa-miR1236 to regulate FEN1 expression but is not associated with Fuchs' endothelial corneal dystrophy.

Fuchs' Endothelial Corneal Dystrophy (FECD) is a genetically complex disorder that affects individuals above 40 years of age; molecular pathogenesis of its associated genes is poorly understood. This study aims at assessing the association of flap endonuclease 1 (FEN1) polymorphisms, c.-69G>A (rs174538) and c.4150G>T (rs4246215) with FECD. Comet assay analysis reaffirmed that endogenous DNA damage was greater in FECD individuals. However, genetic analysis in 79 FECD patients and 234 unrelated control individuals prove that both the FEN1 polymorphisms, c.-69G>A (rs174538) and c.4150G>T (rs4246215), failed to show any genetic association with the FECD disease phenotype. In silico analysis and luciferase reporter assay identified 'G' allele of the 3'UTR located FEN1 polymorphism c.4150G>T as the target for binding of hsa-miR-1236-3p. This study indicates that although FEN1 polymorphisms, c.-69G>A (rs174538) and c.4150G>T (rs4246215) are not genetically associated with FECD, its transcript regulation reported in other diseases such as lung cancer which are genetically associated by rs4246215 could be mediated through miRNA, hsa-miR-1236-3p.