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In response to environmental and cellular cues, the spatiotemporal expression of differentially expressed miRNAs (DEmiRs) during in vitro regeneration of plants is prominent. Nevertheless, the influence of stress conditions on the functional imprints of DEmiRs during plant organogenesis is inadequately understood. Target-mimicry based constitutive diminution of miR167 genes in transgenic tobacco revealed their functional contributions in salt-stress tolerance during organogenesis. Up to 61.6% relative increment in the shoot emergence on leaf explants of miR167 mimic lines (cultured on 12.5 and 25 mM NaCl concentrations) exhibited greater magnitude of organogenesis under stress, most probably through upregulated auxin signalling. Relative expression analysis of auxin transporter genes AUX1, PIN1 and PIN2 revealed synergistic effect of percent miR167 diminution and salt-stress (up to 12.5 mM) resulting into enhanced callogenesis and reduced organogenesis. Biochemical assessment of in vitro grown miR167 mimic shoot initials revealed an increase in the relative water content, chlorophyll and antioxidant activity, which suggested a shift in the molecular equilibrium in response to miR167 diminution-associated signalling pathways. Remarkably, independent miR167 diminution lines exhibited expression variations among associated miR156, miR159, and miR394 and validated by the expression analysis of selected target genes SPL9, ARF6 and ARF8. The expression ratios of these miRNAs revealed their coordinated regulatory network in response to salt-stress during organogenesis. These results demonstrate a link between miR167 diminution and salt-stress tolerance in mimic lines, and suggest that a regulatory shift in the cellular metabolism may contribute to salt-stress tolerance in plants. These observations may create new avenues for strategic utilization of such genic resources for future crop research.

The objectives of this study were to investigate the mutation profiles of targeted genes and copy number variations (CNVs) in normal cytogenetics (CN) pediatric acute myeloid leukemia (AML).This prospective study was conducted from October 2018 to December 2020. The next-generation sequencing (NGS) and chromosomal microarray analyses (CMA) were performed in pediatric CN-AML patients.Out of 94 children (aged ≤18 years), 70 patients with AML (24 excluded) underwent conventional karyotyping/cytogenetic analyses. Forty-five (64.3%) of patients had abnormal/ recurrent cytogenetic abnormalities and 25 (35.7%) had normal cytogenetics. Twenty-three out of 25 CN-AML were further processed for gene mutation profile and CNVs using NGS and CMA, respectively. Twenty-two out of 23 (95.7%) patients were detected to have mutations in various genes. The common mutations were: NRAS, NPM1, CEBPA, KRAS, KIT, RUNX1, NOTCH1, WT1, GATA1, GATA2, FLT3, KMT2D, FLT3-TKD, and PHF6. Copy number variations (CNVs) were detected in nine patients (39%), and eight (34.8%) had a long contiguous stretch of homozygosity (LCSH) /loss of heterozygosity (LOH). An LCSH was detected on chromosomes 5, 7, 11, and 19. The gains were more common than losses (8 vs 2). The gains were observed on chromosomes 8, 9, 14, 19, 21, and 22, and the losses were detected on chromosomes 7 and 10. Monosomy was observed in three patients. Three patients (monosomy7, n = 2, and FLT-ITD, n = 1) were reclassified into the high-risk category. Post-induction, complete remission was achieved in all evaluable patients.CN-AML patients have genetic abnormalities that can be detected by more advanced techniques like NGS and CMA. These genetic abnormalities play a role in risk stratification that may remain hidden in otherwise CN-AML.

Diversity at gene sequence and function level is an evolutionary outcome of a constantly expanding gene family in plants. Genome sequences have provided a platform to comprehend the evolutionary architecture of genes and gene families, especially in plant genera. Apparently, regulatory sequences and the selection of trans-binding proteins have massive impressions of gene expression evolution as compared with a transformation at genic-level itself. Therefore, it becomes essential to comprehensively dissect the genome-wide structure-function evolution of regulatory regions'-binding trans-proteins. WRKY gene family members are developmentally and functionally diverged ancient transcription factors that notably regulates numerous cellular as well as stress responsive phenotypes in plant species. To comprehend the evolutionary consequences of WRKY genes during plant development, a meta-phylogenetic analyses of at least 266 WRKY amino acid sequences of alga, monocot and eudicots plant species was accomplished. Phylogenetic clustering identified assorted groups and sub-groups of WRKY orthologous or paralogous sequences. Paralogous gene divergences of monocot and eudicot species showed strong ‘purifying’ selection during the sequence evolution. Evidently, evolutionary exon-intron structural diversification predominantly arose by ‘exon/intron-gain’ and insertion/deletion during primeval sequence-exonization. The structural DNA-binding domain, and global structures of WRKY proteins are exceedingly divergent and also explicit to the classified phylogenetic clusters. Expression profiling displayed that Group IIe WRKY members are profusely expressed in root tissues of the representative species. Remarkably, the spatial and temporal gene expression patterns of WRKY genes in plants apprise our perception about their contributions in the regulation of cellular functions; and structural-functionalism of these members speculate their probable employment into future crop improvement programs.