کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2190613 1097804 2012 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Germline deletion of FAK-related non-kinase delays post-natal cardiomyocyte mitotic arrest
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی بیولوژی سلول
پیش نمایش صفحه اول مقاله
Germline deletion of FAK-related non-kinase delays post-natal cardiomyocyte mitotic arrest
چکیده انگلیسی

The cardiomyocyte phenotypic switch from a proliferative to terminally differentiated state impacts normal heart development and pathologic myocardial remodeling, yet the signaling mechanisms that regulate this vital process are incompletely understood. Studies from our lab and others indicate that focal adhesion kinase (FAK) is a critical regulator of cardiac growth and remodeling and we found that expression of the endogenous FAK inhibitor, FAK-related non kinase (FRNK) coincided with postnatal cardiomyocyte arrest. Mis-expression of FRNK in the embryonic heart led to pre-term lethality associated with reduced cardiomyocyte proliferation and led us to speculate that the postnatal FRNK surge might be required to promote quiescence in this growth promoting environment. Herein, we provide strong evidence that endogenous FRNK contributes to post-mitotic arrest. Depletion of FRNK promoted DNA synthesis in post-natal day (P) 10 hearts accompanied by a transient increase in DNA content and multi-nucleation by P14, indicative of DNA replication without cell division. Interestingly, a reduction in tri- and tetra-nucleated cardiomyocytes, concomitant with an increase in bi-nucleated cells by P21, indicated the possibility that FRNK-depleted cardiomyocytes underwent eventual cytokinesis. In support of this conclusion, Aurora B-labeled central spindles (a hallmark of cytokinesis) were observed in tetra-nucleated P20 FRNK−/− but not wt cardiomyocytes, while no evidence of apoptosis was observed. Moreover, hearts from FRNK null mice developed ventricular enlargement that persisted until young adulthood which resulted from myocyte expansion rather than myocyte hypertrophy or interstitial growth. These data indicate that endogenous FRNK serves an important role in limiting DNA synthesis and regulating the un-coupling between DNA synthesis and cytokinesis in the post-natal myocardium.


► Focal adhesion kinase-related non-kinase (FRNK) limits perinatal cell cycling.
► Myocytes from FRNK-null mice exhibit sustained DNA synthesis and transient polyploidy.
► FRNK-null hearts exhibit hyperplastic growth.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Molecular and Cellular Cardiology - Volume 53, Issue 2, August 2012, Pages 156–164
نویسندگان
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