Shiojima I, Komuro I, Inazawa J, Nakahori Y, Matsushita I, Abe T, Nagai R, Yazaki Y
Department of Medicine III, University of Tokyo School of Medicine, Japan.
Genomics. 1995 May 1;27(1):204-6. doi: 10.1006/geno.1995.1027.
Homeobox-containing genes play critical roles in regulating tissue-specific gene expression essential for tissue differentiation, as well as determining the temporal and spatial patterns of development. Recently, a human cardiac homeobox-containing gene, CSX, has been isolated. CSX is abundantly expressed in the human heart from fetal stages, suggesting that CSX plays an important role in human heart formation. In the present study, we have determined the chromosomal localization of CSX by fluorescence in situ hybridization techniques and systemic screening of a yeast artificial chromosome library using polymerase chain reaction. By these methods, CSX was mapped to 5q34 of human chromosome 5 near the boundary of 5q34 and 5q35. In this region, another homeobox-containing gene MSX2, which is expressed in various tissues including the conduction system of the developing heart, has been assigned. Localization of CSX and MSX2 to the same region of the human chromosome suggests that these genes may be coordinately regulated during human heart formation.
含同源框的基因在调节组织特异性基因表达中发挥关键作用，这些基因表达对于组织分化至关重要，同时也决定了发育的时空模式。最近，一个含人类心脏同源框的基因CSX已被分离出来。CSX在胎儿期的人类心脏中大量表达，这表明CSX在人类心脏形成中发挥重要作用。在本研究中，我们通过荧光原位杂交技术以及使用聚合酶链反应对酵母人工染色体文库进行系统筛选，确定了CSX的染色体定位。通过这些方法，CSX被定位到人类5号染色体的5q34，靠近5q34和5q35的边界。在该区域，另一个含同源框的基因MSX2已被定位，MSX2在包括发育中心脏传导系统在内的各种组织中表达。CSX和MSX2定位于人类染色体的同一区域，这表明这些基因在人类心脏形成过程中可能受到协同调节。
