Langley R, Leung E, Morris C, Berg R, McDonald M, Weaver A, Parry D A, Ni J, Su J, Gentz R, Spurr N, Krissansen G W
Department of Molecular Medicine, School of Medicine and Health Sciences, University of Auckland, NZ.
DNA Cell Biol. 1998 May;17(5):449-60. doi: 10.1089/dna.1998.17.449.
Herein, we describe the analysis and mapping of cDNA clones encoding variant forms of the human homolog of the canine 180-kDa ribosome receptor (p180). One form, similar to the chicken ES/130 homolog, possesses a large uninterrupted C-terminal region composed predominantly of heptad repeats predicted to form an alpha-helical double-stranded coiled-coil rod. Other forms contain in addition a 10-amino acid consensus motif, NQGKKAEGAQ, repeated up to 54 times in tandem close to the N-terminus. Such repeats in canine p180 represent a ribosome-binding domain. The cDNA hybridized to a major 6-kb transcript in all tissues examined, where very high expression was observed in tissues that carry out a high level of secretion such as pancreas, liver, and placenta. The ES130/p180 gene was mapped to chromosome 20p12, and a potential pseudogene appears to reside on chromosome 7. In summary, the data suggest that p180 exists in humans in different forms because of complete removal of tandem repeats, or partial intraexonic splicing, creating different repeat lengths with potentially novel ribosome-binding characteristics.
在此，我们描述了编码犬类180-kDa核糖体受体（p180）人类同源物变体形式的cDNA克隆的分析和定位。一种形式类似于鸡ES/130同源物，具有一个大的不间断C末端区域，主要由预测形成α-螺旋双链卷曲螺旋杆的七肽重复序列组成。其他形式还包含一个10个氨基酸的共有基序NQGKKAEGAQ，在靠近N末端处串联重复多达54次。犬类p180中的此类重复序列代表核糖体结合结构域。该cDNA与所有检测组织中的一个主要6-kb转录本杂交，在进行高水平分泌的组织如胰腺、肝脏和胎盘中观察到非常高的表达。ES130/p180基因定位于20号染色体p12区域，并且一个潜在的假基因似乎位于7号染色体上。总之，数据表明由于串联重复序列的完全去除或部分外显子内剪接，p180在人类中以不同形式存在，从而产生具有潜在新核糖体结合特征的不同重复长度。
