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H B Jie

Publications and source records attributed to H B Jie.

4 recordsLinked to original sources

Molecular cloning and expression pattern of porcine myeloid DAP12-associating lectin-1.

DAP12 is an ITAM-bearing membrane protein that is associated with activating receptors in natural killer cells, granulocytes, macrophages, and monocytes. Myeloid DAP12-associating lectin-1 (MDL-1) is a type II membrane protein that associates with DAP12. In this study, we report the molecular cloning of two isoforms of porcine MDL-1 cDNA from pulmonary alveolar macrophages. The porcine MDL-1 short form has 165 amino acids and 70% sequence identity with the mouse MDL-1 short form. The long form has 20 more amino acids in the stalk region and 71% sequence identity with human MDL-1 and 67% with the mouse MDL-1 long form. Porcine MDL-1 contains a conserved lysine in the transmembrane domain. There are six putative N-linked glycosylation sites in the MDL-1 long form. MDL-1 transcripts were detected exclusively in macrophages and monocytes by RT-PCR. When transfected into 293 cells, porcine MDL-1 is expressed on the cell surface associated with DAP12.

Amino Acid Sequence↗

Molecular cloning and characterization of pig immunoreceptor DAP10 and NKG2D.

Pig immunoreceptor DAP10 cDNA was cloned from a peripheral blood lymphocyte (PBL) cDNA library using human DAP10 cDNA as a probe. The length of the pig DAP10 cDNA is 465 bp and it contains an open reading frame of 237 bp. The predicted polypeptide sequence is 79 amino acids, consisting of an 18-amino acid leader, a 16-amino acid extracellular domain, a 24-amino acid transmembrane segment, and a 21-amino acid cytoplasmic domain. The amino acid sequence of pig DAP10 has 68% and 78% sequence identity with human DAP10 and mouse DAP10, respectively. Pig DAP10 has a conserved aspartic acid in the transmembrane domain, two cysteines in the extracellular domain, and a phophatidylinositol-3 kinase-binding site (YxxM) in the cytoplasmic region. Genomic organization reveals that pig DAP10 comprises four exons and three introns. Pig DAP10 and DAP12 are genetically linked on Chromosome (Chr) 6 at 6q21 in opposite transcriptional orientation, separated by 152 bp. In Northern blot analysis, DAP10 transcripts were detected predominantly in lymphohematopoietic tissues. Pig NKG2D cDNA has an open reading frame of 642 bp. Its expected polypeptide sequence is 214 amino acids. Pig NKG2D has 66% sequence identity with human NKG2D and 56% identity with mouse NKG2D. The NKG2D gene maps to pig Chr 5q25. RT-PCR analysis reveals that pig NKG2D transcripts are expressed in PBLs, NK cells, macrophages, and monocytes. When transiently transfected into COS-7 cells, pig NKG2D requires DAP10 for cell surface expression.

Amino Acid Sequence↗

Molecular cloning, gene structure, and expression pattern of pig immunoreceptor DAP12.

Natural killer (NK) cells express receptors for MHC class I that contain immunoreceptor tyrosine-based inhibitory motif (ITIM) sequences in their cytoplasmic domain. Whereas these receptors inhibit NK cell cytotoxicity, certain isoforms of these NK receptors (e.g., KIR2DS, CD94/NKG2C, and Ly49D) do not have ITIMs, but associate with DAP12 and activate NK cell function. We cloned pig DAP12 cDNA from a pig peripheral blood lymphocyte (PBL) cDNA library using human DAP12 cDNA as a probe. The length of the pig DAP12 cDNA is 526 bp and contains an open reading frame of 324 bp. It has 79% identity with the human DAP12 cDNA sequence in the coding region and 73% identity with mouse DAP12 cDNA. The predicted polypeptide sequence of pig DAP12 is 108 amino acids, being composed of a 23-amino acid leader, a 14-amino acid extracellular domain, a 24-amino acid transmembrane segment, and a 47-amino acid cytoplasmic region. The amino acid sequence of pig DAP12 has 74% and 71% sequence identity with human DAP12 and mouse DAP12, respectively. Pig DAP12 has a conserved aspartic acid in the transmembrane region, and two conserved cysteine residues in the extracellular domain. It also contains an immunoreceptor tyrosine-based activation motif sequence in the cytoplasmic region. Genomic organization reveals that pig DAP12 consists of five exons and four introns. Southern blot analysis of pig genomic DNA revealed that DAP12 is a single-copy gene. In Northern blot analysis, DAP12 transcripts were detected in spleen, liver, thymus, and lymph node. DAP12 transcripts are expressed not only in PBLs, but also in granulocytes, macrophages, and monocytes.

Adaptor Proteins, Signal Transducing↗