Identification, cloning and characterization of a novel nuclear protein, HA95, homologous to A-kinase anchoring protein 95
Identification, cloning and characterization of a novel nuclear protein, HA95, homologous to A-kinase anchoring protein 95
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DOI：
10.1016/s0248-4900(00)88761-4
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发表时间：
2000-01-01
影响因子：
2.7
通讯作者：
Skålhegg, BS
中科院分区：
文献类型：
--
作者：
Orstavik, S;Eide, T;Skålhegg, BS
以前，我们已经从人的核中鉴定了针对cAMP(CAMP)依赖的蛋白激酶(PKA)-II型到有丝分裂时的染色质/纺锤体浓缩区域的核AKAP95，在这里我们报道了一个新的核蛋白的克隆，其表观分子量与AKAP95相似，命名为HA95(与AKAP95同源)。HA95基因编码646个氨基酸的蛋白质，与AKAP95推导的氨基酸序列有61%的同源性。HA95基因位于染色体19p13.1上，紧靠AKAP95基因上游。HA95和AKAP95基因都包含14个外显子，编码各自蛋白质的相似区域，表明之前的基因复制事件是两个串联基因的起源。尽管它们表面上相似，但HA95在体外并不结合RII。HA95在其N-末端区域含有一个假定的核定位信号。在HA95融合到绿色荧光蛋白或c-myc表位的细胞中，它仅定位于细胞核。在细胞核中，HA95蛋白被发现为相互直接关联或通过其他核蛋白间接关联的复合体。在间期，HA95和AKAP95是共定位的，但这两个蛋白在生化上没有关联。在中期，这两种蛋白质与浓缩的染色体共定位。HA95和AKAP95在序列和定位上的相似性表明，这两个分子构成了一个可能具有相关功能的新的核蛋白家族。2000年(C)《爱思唯尔爱思唯尔公司的科学与医学版》。
Previously, we have identified and characterized nuclear AKAP95 from man which targets cyclic AMP (cAMP)-dependent protein kinase (PKA)-type II to the condensed chromatin/spindle region at mitosis, Here we report the cloning of a novel nuclear protein with an apparent molecular mass of 95 kDa that is similar to AKAP95 and is designated HA95 (homologous to AKAP95). HA95 cDNA sequence encodes a protein of 646 amino acids that shows 61% homology to the deduced amino acid sequence of AKAP95. The HA95 gene is located on chromosome 19p13.1 immediately upstream of the AKAP95 gene. Both HA95 and AKAP95 genes contain 14 exons encoding similar regions of the respective proteins, indicating a previous gene duplication event as the origin of the two tandem genes. Despite their apparent similarity, HA95 does not bind RII in vitro. HA95 contains a putative nuclear localization signal in its N-terminal domain. It is localized exclusively into the nucleus as demonstrated in cells transfected with HA95 fused to either green fluorescence protein or the c-myc epitope. In the nucleus, the HA95 protein is found as complexes directly associated with each other or indirectly associated via other nuclear proteins. In interphase, HA95 is co-localized with AKAP95, but the two proteins are not biochemically associated. At metaphase, both proteins co-localize with condensed chromosomes. The similarity in sequence and localization of HA95 and AKAP95 suggests that the two molecules constitute a novel family of nuclear proteins that may exhibit related functions. 2000 (C) Editions scientifiques et medicales Elsevier SAS.