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目的分离人染色体８ｐ１１．２亚带ＡＮＫ１位点附近区域基因的表达序列。方法采用ｃＤＮＡ选择法从定位于该区域的人工酵母染色体（ＹＡＣ）中分离基因的表达序列，并从分离的表达序列中选取１个序列用于筛选人胎脑ｃＤＮＡ文库。结果获得７个表达序列，其中５个可与目的ＹＡＣ反杂交。所得的表达序列ＢＨＬＣ１５２与鼠的ＣＡｒＧ盒结合因子基因高度同源，ＢＨＬＣ７４与编码心室肌肌球蛋白的碱性轻链１（ＭＬＣ１）基因高度同源，表明ＢＨＬＣ７４可能编码一种ＭＬＣ１的同工蛋白。分离的其它表达序列与数据库内一些位置和功能尚不清楚的表达序列标签（ｅｘｐｒｅｓｅｄｓｅ－ｑｕｅｎｃｅｔａｇ，ＥＳＴ）仅有部分同源性。用表达序列ＢＨＬＣ１１９筛选人胎脑ｃＤＮＡ文库，获得１个插入片段长１９５１ｂｐ的克隆，序列分析表明它编码１７４个氨基酸，该序列与所有已知的蛋白质序列无同源性。Ｎｏｒｔｈｅｒｎ印迹分析结果显示，在人胎脑总ＲＮＡ中呈现１条约３．５ｋｂ带；组织表达分析表明，此系一广泛表达的基因。结论ＢＨＬＣ７４可能作为与８ｐ相关的心脏病候选基因，其它序列至少可以作为定位在ＡＮＫ１位点附近区域的肿瘤抑制基因的初筛基因。
Objective To isolate the sequence of the gene in the vicinity of the ANK1 locus on chromosome 8p11.2. Methods The cDNA was isolated from the artificial yeast chromosome (YAC) located in this region and one sequence was selected from the isolated expression sequences for screening the human fetal brain cDNA library. As a result, seven expression sequences were obtained, of which five were hybridized with the desired YAC. The resulting expression sequence BHLC152 is highly homologous to the murine CArG box binding factor gene and BHLC74 is highly homologous to the ventricular myoglobin-encoding basic light chain 1 (MLC1) gene, indicating that BHLC74 may encode a co-protein of MLC1 . The other expressed sequences separated only partially homologues from the expresedse-quencetag (EST) in some unknown positions in the database. The human fetal brain cDNA library was screened with the expression sequence BHLC119 to obtain a 1951bp cloned clone. The sequence analysis indicated that it encodes 174 amino acids, which has no homology with all known protein sequences. Northern blot analysis showed that there was one 3.5kb band in total RNA of human fetal brain. Tissue expression analysis showed that this gene was a widely expressed gene. Conclusions BHLC74 may serve as a candidate gene for heart disease associated with 8p, and other sequences may serve as primary screening genes for tumor suppressor genes located at least in the vicinity of the ANK1 locus.