Short-Term Effects of Y-27632, a Rho-Associated Protein Kinase Inhibitor, on Chromatin Supraorganization and DNA Amount in Epithelial Cells of the Rat Cornea and Limbus

Abstract

Changes in chromatin supraorganization and DNA amount, such as seen in this study, are indicative of cell proliferation and do not seem to be associated with disturbances in gene activity and transcription of DNA.

Nuclear parameters and chromatin remodeling in epithelial cells and lymphocytes from the palpebral conjunctiva of dogs with keratoconjunctivitis sicca

“…18 The major component of the nucleus is chromatin, a malleable fiber that results from the assembly of DNA with histones and other nucleoproteins. 1,19,20 The degree of DNA affinity for histones organizes the genome into either open/relaxed (euchromatin) or compacted chromatin (heterochromatin) and thus regulates the accessibility of genes for transcription, replication, and repair. 19 The process of interaction between DNA and histones is dynamic and mediated by ATP-dependent nucleosome remodeling complexes and by epigenetic enzymes, which are up-or downregulated by microenvironmental stimuli.…”

“…19 The process of interaction between DNA and histones is dynamic and mediated by ATP-dependent nucleosome remodeling complexes and by epigenetic enzymes, which are up-or downregulated by microenvironmental stimuli. 17,[19][20][21][22] There is emerging evidence that changes in the microenvironment surrounding the cells elicit the chromatin to remodel from a more compacted to a more relaxed state and vice versa. [22][23][24] Remodeling alters the functionality of chromatin, the expression of genes, and the synthesis of proteins, and can contribute to the progression of diseases and/ or syndromes.…”

“…[24][25][26][27][28][29] Nuclear size and shape, DNA content (ploidy), and chromatin remodeling can be studied in cytological preparations using video image analysis and the Feulgen reaction. 20,30 Video image analysis in Feulgen-stained preparations is recommended to evaluate defined cell populations. 20 In addition to reporting on supraorganizational and functional parameters of the chromatin fiber (compaction and texture), the method provides information on the geometry of the cell nucleus and allows quantification of DNA ploidy by generating an equivalent cytometric of chromosomal ploidy.…”

“…20,30 Video image analysis in Feulgen-stained preparations is recommended to evaluate defined cell populations. 20 In addition to reporting on supraorganizational and functional parameters of the chromatin fiber (compaction and texture), the method provides information on the geometry of the cell nucleus and allows quantification of DNA ploidy by generating an equivalent cytometric of chromosomal ploidy. 20,30 The Feulgen reaction is a stoichiometric DNA-staining technique that consists of two steps.…”

“…20 In addition to reporting on supraorganizational and functional parameters of the chromatin fiber (compaction and texture), the method provides information on the geometry of the cell nucleus and allows quantification of DNA ploidy by generating an equivalent cytometric of chromosomal ploidy. 20,30 The Feulgen reaction is a stoichiometric DNA-staining technique that consists of two steps. 20,30,31 In the first step, the DNA is submitted to acid hydrolysis to split off the purine bases from the double-stranded DNA.…”