MiRNA-Based Regulation of Hemostatic Factors through Hepatic Nuclear Factor-4 Alpha
PLOS ONE
Authors: Salloum-Asfar, Salam; Arroyo, Ana B.; Teruel-Montoya, Raul; Garcia-Barbera, Nuria; Roldan, Vanessa; Vicente, Vicente; Martinez, Constantino; Gonzalez-Conejero, Rocio
Abstract
MiRNAs have been reported as CIS-acting elements of several hemostatic factors, however, their mechanism as TRANS-acting elements mediated by a transcription factor is little known and could have important effects. HNF4 alpha has a direct and important role in the regulation of multiple hepatic coagulation genes. Previous in vitro studies have demonstrated that miR-24-3p and miR-34a-5p regulate HNF4A expression. Here we aimed to investigate the molecular mechanisms of miR-24 and miR-34a on coagulation through HNF4A. Transfections with miR-24 and miR-34a in HepG2 cells decreased not only HNF4A but also F10, F12, SERPINC1, PROS1, PROC, and PROZ transcripts levels. Positive and significant correlations were observed between levels of HNF4A and several hemostatic factors (F5, F8, F9, F11, F12, SERPINC1, PROC, and PROS1) in human liver samples (N = 104). However, miR-24 and miR-34a levels of the low (10th) and high (90th) percentiles of those liver samples were inversely correlated with HNF4A and almost all hemostatic factors expression levels. These outcomes suggest that miR-24 and miR-34a might be two indirect elements of regulation of several hemostatic factors. Additionally, variations in miRNA expression profiles could justify, at least in part, changes in HNF4A expression levels and its downstream targets of coagulation.
A novel mutation Gly222Arg in PROS1 causing protein S deficiency in a patient with pulmonary embolism
JOURNAL OF CLINICAL LABORATORY ANALYSIS
Authors: Xu, Jingqing; Peng, Gehong; Ouyang, Yao
Abstract
Background Thrombophilia is becoming a more frequently reported disorder these years. Hereditary protein S deficiency is one of the anticoagulant deficiencies that eventually results in thrombophilia. Case presentation A 24-year-old male patient was suffering from unexplained thrombosis for the second time with a family history of deep venous thrombosis. Screening tests for anticoagulant proteins found the activity of protein S markedly lowered (5.0%). The patient was discharged after anticoagulation treatment. Four years later, the review still showed the activity of protein S in his plasma decreased (16.0%). Molecular genetic analysis revealed him homozygous for a missense mutation, c.664G>A, in the exon7 of PROS1. The mutation discovered here is the first mutation affecting the codon 222 of PROS1. This mutation results in the replacement of the glycine at the codon 222 of protein S with arginine, leading to a reduction of protein S function. Conclusions The finding of this mutation may help with the understanding of the mechanism of protein S deficiency, especially in the Chinese population.