Murine Hn1 on Chromosome 11 is expressed in hemopoietic and brain tissues
Murine Hn1 on Chromosome 11 is expressed in hemopoietic and brain tissues
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DOI：
10.1007/s003359900540
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发表时间：
1997-09-01
期刊：
影响因子：
2.5
通讯作者：
Chui, DHK
中科院分区：
文献类型：
--
作者：
Tang, WZ;Lai, YH;Chui, DHK
如前所述（Chui等，1995），从鼠第9天卵黄囊血岛衍生的原始红系细胞hgt 11 cDNA文库中分离出一个新的1.4-kb cDNA克隆。该克隆以大约每5000个噬菌体噬斑一个的频率存在于文库中。它在许多胎儿和成人组织中表达，在造血细胞和胎儿脑中表达水平最高。我们将编码cDNA产物的基因命名为造血和神经表达序列1，Hnl。在这里，我们报告的核苷酸序列，组织mRNA的分布，和染色体定位的Hnl。图1显示了编号为1356 bp的Hnl（GenBank登录号U90123）的核苷酸序列，具有编码具有154个氨基酸的推定肽的开放阅读框。为了确定有义链序列，从小鼠成纤维细胞3 T3细胞中提取的富含poly-A的RNA用作逆转录聚合酶链反应（RT-PCR）的模板，在Hnl的nt 641-1004侧翼设置两个寡核苷酸引物。结果与图1所示的序列一致，即有义链。Hnl与GenBank数据库中其他已知基因没有显著同源性，用”BLASTX”和”BLASTX”程序通过美国国家生物技术信息中心的BLAST服务器进行检索。然而，Hn 1与许多小鼠表达序列标签（EST）和至少30个来自许多人cDNA文库的EST具有显著的同源性，所述人cDNA文库包括胎儿、婴儿和成人脑、胎儿肝和脾、白色细胞、胎盘、内皮细胞、肺、前列腺和睾丸。如图2所示，用对应于nt 641-1167的PCR产生的放射性探针，在所有检查的组织中观察到1.4-kb片段。在造血细胞中发现了最高水平的表达，包括第10天卵黄囊血岛衍生的循环成红细胞、第13天胎儿肝脏（胎儿红细胞生成的主要部位）、成人骨髓和脾脏。在第17天胎儿脑中的表达也非常高，而在成人脑中的表达相当低。Hnl还在鼠红白血病（MEL）、骨髓（FDC-P1）、骨髓单核细胞（WEHI-3）、T（EL 4）和Pre-B（70 Z/3）细胞系以及BL 3造血多能细胞系（Wong等，1994）、3 T3成纤维细胞系和PCC 3胚胎干细胞系中表达。来自胎儿和成人组织的RNA的北方印迹分析，与PCR产生的探针杂交，所述探针对应于从nt 1043到3 '末端的Hnl的Pst I片段，与用于遗传定位Hnl的探针相同（见下文），产生相同的
A novel 1.4-kb cDNA clone was isolated from a murine day 9, yolk sac blood islands-derived, primitive erythroid cell hgtll cDNA library as previously described (Chui et al. 1995). The clone is present in the library at a frequency of approximately one per 5000 phage plaques. It is expressed in many fetal and adult tissues, with highest levels of expression found in hemopoietic cells and fetal brain. We have designated the gene encoding the cDNA product as hemopoietic-and neurologic-expressed sequence 1, Hnl. Here we report the nucleotide sequence, tissue mRNA distribution, and chromosomal localization of Hnl. Figure 1 shows the nucleotide sequence of Hnl (GenBank accession number U90123) numbering 1356 bp, with an open reading frame coding for a putative peptide with 154 amino acids. To ascertain the sense strand sequence, poly-A-rich RNA extracted from murine fibroblast 3T3 cells was used as the template for reverse transcription-polymerase chain reaction (RT-PCR), with two oligonucleotide primers flanking nt 641-1004 of Hnl. The results are consistent with the sequence as illustrated in Fig. 1, being the sense strand. There is no significant homology between Hnl and other known genes in the GenBank database search, with the" BLASTN" and" BLASTX" programs through the National Center for Biotechnology Information BLAST server. However, Hnl shares significant homology with many murine expressed sequence tags (ESTs) and at least 30 ESTs derived from many human cDNA libraries, including fetal, infant, and adult brains, fetal liver and spleen, white blood cells, placenta, endothelial cells, lung, prostate gland and testes.Northern blotting analysis was carried out with total cellular RNAs extracted from fetal and adult tissues. As shown in Fig. 2, with a PCR-generated radioactive probe corresponding to nt 641-1167, a 1.4-kb fragment was observed in all tissues examined. The highest levels of expression were found in hemopoietic cells, including day 10 yolk sac blood island-derived circulating erythroblasts, day 13 fetal liver which is the main site of fetal erythropoiesis, adult bone marrow, and spleen. The expression is also very high in day 17 fetal brain, while the expression in adult brain is considerably lower. Hnl is also expressed in murine erythroleukemia (MEL), myeloid (FDC-P1), myelomonocytic (WEHI-3), T (EL4), and Pre-B (70Z/3) cell lines as well as in the BL3 hemopoietic multipotential cell line (Wong et al. 1994), 3T3 fibroblast cell line, and PCC3 embryonic stem cell line. Northern blot analysis of RNAs from both fetal and adult tissues, hybridized with a PCR-generated probe corresponding to the PstI fragment of Hnl from nt 1043 to the 3'terminus, identical to that used to genetically map Hnl (see below), yielded identical