Mohin Sapara

Introduction Epigenetic regulation is one of the most fundamental mechanisms controlling gene expression in human cells. Although every somatic cell contains nearly identical DNA sequences, different cell types exhibit highly specialized functions because distinct transcriptional programs are activated or suppressed through chromatin remodeling. Histone modifications represent a major component of this epigenetic control system, regulating chromatin accessibility and transcription factor recruitment. Among the most important histone-modifying enzymes involved in enhancer activation is KMT2D, also known as Lysine Methyltransferase 2D or MLL2. KMT2D encodes a large nuclear histone methyltransferase located on chromosome 12q13.12. The protein belongs to the COMPASS-like family of chromatin regulators and primarily catalyzes mono- and di-methylation of histone H3 lysine 4 (H3K4me1 and H3K4me2). These histone modifications are characteristic epigenetic signatures of active enhancers, which ...

Abstract High Mobility Group Nucleosome-binding protein 5 (HMGN5) has emerged as an important chromatin architectural regulator involved in the epigenetic control of transcription, chromatin accessibility, and oncogenic transformation. Recent evidence demonstrates that aberrant HMGN5 expression contributes significantly to breast cancer progression through modulation of chromatin dynamics and activation of proliferation-associated transcriptional programs. HMGN5 belongs to the HMGN family of non-histone chromosomal proteins that interact directly with nucleosomes and regulate higher-order chromatin structure. Unlike sequence-specific transcription factors, HMGN proteins exert genome-wide regulatory effects by altering nucleosomal stability, histone modification accessibility, and transcriptional competency. In breast carcinoma, elevated HMGN5 expression correlates with aggressive clinical phenotypes, enhanced proliferative capacity, increased DNA replication activity, and poor prognosi...