CAJ | 학술논문

采用touchdown PCR和RACE技术，获得了两条尼罗罗非鱼MHC IA基因3’端的新序列，其长度均为957 bp，分别命名为orni-DAA倡0101和orni-DAA倡0102，其分别编码了两种新发现的等位基因亚型。两条新序列均包含666 bp的CDS区和291 bp的3’-UTR区，CDS区包含了部分多肽结合区、全部的IGC区以及跨膜区和胞质区。同源性比对显示，cDNA序列分别在388 bp和426 bp处发生了碱基转换，而其编码的氨基酸序列在第130位点存在谷氨酸与赖氨酸的差异。首次发现相对保守的IGC区也存在变异。研究结果对于揭示尼罗罗非鱼MHC IA基因的多态性及其与高抗病性的相关性有重要价值。
채용touchdown PCR화RACE기술，획득료량조니라라비어MHC IA기인3’단적신서렬，기장도균위957 bp，분별명명위orni-DAA창0101화orni-DAA창0102，기분별편마료량충신발현적등위기인아형。량조신서렬균포함666 bp적CDS구화291 bp적3’-UTR구，CDS구포함료부분다태결합구、전부적IGC구이급과막구화포질구。동원성비대현시，cDNA서렬분별재388 bp화426 bp처발생료감기전환，이기편마적안기산서렬재제130위점존재곡안산여뢰안산적차이。수차발현상대보수적IGC구야존재변이。연구결과대우게시니라라비어MHC IA기인적다태성급기여고항병성적상관성유중요개치。
In this study, The PCR products by rapid amplification of cDNA ends polymerase chain reaction ( RACE-PCR) and touchdown PCR from the tilapia MHC class IA gene 3 ’ end were spliced and sequenced.The two 957 bp cDNA sequences were newly obtained and named orni-DAA*0101 and orni-DAA*0102, respectively.They encode two newly discovered subtypes of the alleles from tilapia MHC class IA gene.Both of the two cDNA fragments contain a 666 bp CDS region which consists of:a partial peptide-binding region, an immunoglobulin-like region, a transmem-brane region, a cytoplasmic region and with a 291 bp 3’-UTR region.Homologous comparison shows that the cDNA sequences have two transition sites in 388 bp and 426 bp, but the amino acid sequences have only one single amino acid changed in the 130th site:the differences between Glutamic and Lysine.It is the first time to discover an amino acid variation in the relatively conservative IGC domain.The information newly obtained has an important value to reveal the relationship between high disease-resistance and polymorphism of tilapia MHC class IA gene.