Heart-type fatty acid binding proteins are upregulated during terminal differentiation of mouse cardiomyocytes, as revealed by proteomic analysis
Heart-type fatty acid binding proteins are upregulated during terminal differentiation of mouse cardiomyocytes, as revealed by proteomic analysis
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DOI：
10.1007/s00441-004-0881-y
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发表时间：
2004-06-01
影响因子：
3.6
通讯作者：
Lee, KKH
中科院分区：
文献类型：
--
作者：
Tang, MK;Kindler, PM;Lee, KKH
在出生时，小鼠新生心脏中的心肌细胞仍然保持其增殖能力。然而，这只持续几天，然后心肌细胞不可逆转地失去了分裂的潜力。目前还没有完全了解哪些因素参与了心肌细胞增殖的停止。使用增殖细胞核抗原（PCNA）抗体，我们建立了心肌细胞可以广泛地在2天大的小鼠新生儿心脏和在较小程度上在6天大的心脏。到第13天，心肌细胞大多停止分裂。比较二维凝胶电泳（2-DE）进行总蛋白提取2天和13日龄的心脏，以确定可能参与抑制心肌细胞增殖的肽。使用基质辅助激光解吸电离质谱（MALDI-TOF），我们确定了两个蛋白质点，具有相同的分子量（约14 kDa），但不同的pIs（5.9和6.1）。质谱分析确定蛋白质是心脏型脂肪酸结合蛋白（H-FABP）的同种型。pI 6.1 H-FABP也称为乳腺源性生长抑制剂（MDGI; Specht et al. 1996）。MGDI是一种乳腺肿瘤生长抑制基因，能够抑制肿瘤细胞增殖（Huynh et al. 1995）。两种H-FABP亚型在2日龄心脏中表达，但在13日龄心脏中强烈上调。我们研究是否H-FABP和PCNA共表达在2，6和13日龄的心脏组织切片，使用MDGI抗体。该抗体可以检测两种形式的H-FABPs。已确定H-FABP表达的增加与PCNA表达的减少之间存在相关性。因此，我们初步提出H-FABP亚型参与调节小鼠新生心脏心肌细胞的生长和分化。
At birth, the cardiomyocytes in the mouse neonatal heart still retain their ability to proliferate. However, this lasts only a few days and then the cardiomyocytes irreversibly lose their potential to divide. It is still not fully understood what factors are involved in the cessation of cardiomyocyte proliferation. Using proliferating cell nuclear antigen (PCNA) antibodies, we established that cardiomyocytes could divide extensively in 2-day-old mouse neonatal hearts and to a lesser extent in 6-day-old hearts. By 13 days, the cardiomyocytes have mostly stopped dividing. Comparative two-dimensional gel electrophoresis (2-DE) was performed on total proteins extracted from the 2-day- and 13-day-old hearts, in order to identify peptides that might be involved in the inhibition of cardiomyocyte proliferation. Using matrix-assisted laser desorption ionization mass spectroscopy (MALDI-TOF), we identified two protein spots that have the same molecular weight (approximately 14 kDa) but different pIs (5.9 and 6.1). Mass spectra analysis determined the proteins to be isoforms of the heart-type fatty acid binding protein (H-FABP). The pI 6.1 H-FABP is also known as mammary-derived growth inhibitor (MDGI; Specht et al. 1996). MGDI is a breast tumour growth suppressor gene capable of inhibiting tumour cell proliferation (Huynh et al. 1995). Both H-FABP isoforms were expressed in 2-day-old hearts but became strongly upregulated in 13-day-old hearts. We examined whether H-FABPs and PCNA were coexpressed in 2-, 6- and 13-day-old heart histological sections, using MDGI antibodies. The antibody could detect both forms of H-FABPs. It was established that there was a correlation between an increase in H-FABP expression and a decrease in PCNA expression. Hence, we tentatively propose that H-FABP isoforms are involved in regulating cardiomyocyte growth and differentiation in mouse neonatal hearts.