Материал из hpluswiki
Перейти к навигации Перейти к поиску

Actin, gamma-enteric smooth muscle precursor (Alpha-actin-3) (Gamma-2-actin) (Smooth muscle gamma-actin) [Contains: Actin, gamma-enteric smooth muscle, intermediate form] [ACTA3] [ACTL3] [ACTSG]


Expression of genes encoding smooth muscle contractile proteins in vaginal tissue of women with and without pelvic organ prolapse.

We hypothesize that the expression of genes encoding vaginal smooth muscle (SM) contractile proteins is altered in patients with pelvic organ prolapse (POP) and is influenced by age and menopausal status. We aim to analyze the expression of SM-myosin heavy chain (MHY11), caldesmon (CALD1), SM gamma-actin (ACTG2), and tropomyosin (TPM1), in premenopausal and postmenopausal women with advanced POP and asymptomatic controls. During total hysterectomy we collected anterior vaginal wall biopsy samples from 55 women, 37 premenopausal (23 patients and 14 controls), and 18 postmenopausal women (13 patients and 5 controls). Total mRNA from the tissues was quantified by real-time RT-PCR. MHY11 gene expression was down-regulated in premenopausal POP patients compared to premenopausal controls (fivefold, P = 0.002). In the postmenopausal groups, we observed a sixfold increase in the CALD1 gene expression in POP patients compared to asymptomatic controls (P = 0.03). The gene expression of CALD1, ACTG2, and TPM1 was significantly down-regulated in vaginal tissue of healthy women after menopause (P < 0.05). Dysregulation of the vaginal SM content in POP patients involves alteration of different cellular pathways according to age and menopausal status.

MeSH Terms

  • Actins
  • Adult
  • Aged
  • Aging
  • Biopsy
  • Calmodulin-Binding Proteins
  • Case-Control Studies
  • Down-Regulation
  • Female
  • Gene Expression Regulation
  • Humans
  • Middle Aged
  • Muscle Contraction
  • Muscle Proteins
  • Muscle, Smooth
  • Myosin Heavy Chains
  • Pelvic Organ Prolapse
  • Postmenopause
  • RNA, Messenger
  • Tropomyosin
  • Vagina

Stability of housekeeping gene expression in the rat retina during exposure to cyclic hyperoxia.

Recent evidence suggests a genetic component to oxygen-induced retinopathy (OIR), a robust experimental model of human retinopathy of prematurity. OIR lends itself well to quantitative analysis of gene expression in rodents with well-defined genetic backgrounds. Such analysis by real-time reverse transcription polymerase chain reaction (RT-PCR) requires the use of reference genes as internal standards for purposes of normalization. We sought to identify housekeeping genes showing stable retinal expression across different rat strains and developmental stages, that were not regulated by oxygen tension. Real-time RT-PCR was used to examine in normal (control) neonatal rat retina the expression of five candidate reference genes: acidic ribosomal phosphoprotein (ARBP), cyclophilin A (CYCA), gamma 2 actin (ACTG2), hypoxanthine guanine phosphoribosyltransferase (HPRT), and RNA polymerase 2 (RNAP2). ACTG2 was poorly expressed, whereas quantification of CYCA was confounded by putative amplification of pseudogenes. Expression of ARBP, HPRT, and RNAP2 was then quantified in dissected retinas from neonatal rats of three inbred strains (Fischer 344, Sprague Dawley, and Dark Agouti) under two different conditions of exposure to inspired oxygen (exposure to room air for 14 days from birth; exposure to cyclic hyperoxia for 14 days from birth). The average variation in relative expression between each pair of these three genes within each of the six cDNA test samples was used to assess stability of gene expression, relative to a standard retinal cDNA pool. The relative expression values for ARBP and HPRT were more closely correlated (r2=0.80) than were those for either gene with RNAP2 (ARBP and RNAP2: r2=0.31; HPRT and RNAP2: r2=0.25). There was little variation among the six experimental groups for the normalized expression of ARBP or HPRT (p>0.05). In contrast, the normalized expression of RNAP2 varied significantly amongst experimental groups: Within each strain, expression was higher in the oxygen-exposed group than in the room air-exposed group (p<0.05). We conclude that ARBP and HPRT exhibit expression that is sufficiently stable under conditions of varying oxygen tension, to permit their use as housekeeping genes in at least one model of OIR in the neonatal rat.

MeSH Terms

  • Aging
  • Animals
  • Gene Expression
  • Hyperoxia
  • Hypoxanthine Phosphoribosyltransferase
  • Oxygen
  • Periodicity
  • Phosphoproteins
  • Rats
  • Rats, Inbred Strains
  • Retina
  • Reverse Transcriptase Polymerase Chain Reaction
  • Ribosomal Proteins