Two variable lymphocyte receptor genes of the inshore hagfish are located far apart on the same chromosome
Two variable lymphocyte receptor genes of the inshore hagfish are located far apart on the same chromosome
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DOI：
10.1007/s00251-007-0200-3
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发表时间：
2007-04-01
期刊：
影响因子：
3.2
通讯作者：
Kasahara, Masanori
中科院分区：
文献类型：
--
作者：
Kasamatsu, Jun;Suzuki, Takashi;Kasahara, Masanori
可变淋巴细胞受体（VLR）通过组装高度多样的富含亮氨酸重复序列（LRR）模块产生巨大的多样性，并可能在无颌脊椎动物中作为抗原受体发挥作用。盲鳗是沿着七鳃鳗一起构成无颌脊椎动物的主要现存成员，它们具有两个被命名为VLRA和VLRB的VLR基因，而在七鳃鳗中仅鉴定出一个VLR基因。在本研究中，我们通过荧光原位杂交（FISH）表明，盲鳗VLRA和VLRB位于同一染色体上，但彼此相距甚远。可用的近海盲鳗互补DNA序列的分析表明，VLRA和VLRB不共享具有相同核苷酸序列的LRR模块。VLRA和VLRB的物理分离与这一观察结果一致，表明两个VLR基因作为单独的单位发挥作用。在这项研究中开发的FISH协议应该是有用的无颌染色体组的分析。
Variable lymphocyte receptors (VLR) generate enormous diversity through assembling highly diverse leucine-rich repeat (LRR) modules and presumably function as antigen receptors in jawless vertebrates. The hagfish, which constitute major extant members of jawless vertebrates along with lampreys, have two VLR genes designated VLRA and VLRB, whereas only a single VLR gene has been identified in the lamprey. In the present study, we show by fluorescence in situ hybridization (FISH) that hagfish VLRA and VLRB are located on the same chromosome, but are far apart from each other. Analysis of available inshore hagfish complementary DNA sequences indicates that VLRA and VLRB do not share a LRR module with an identical nucleotide sequence. Physical separation of VLRA and VLRB is consistent with this observation and indicates that the two VLR genes function as separate units. The FISH protocol developed in this study should be useful for the analysis of the agnathan genome.