Cloning, sequence characterization, and expression patterns of members of the porcine TSSK family.

Testis-specific serine kinases (TSSKs) are a family of serine/threonine kinases highly expressed in the testes that are responsible for regulating many spermatogenesis-related protein activities. Mutations in this family have a positive relationship with oligospermia and azoospermia in human and mouse. Here, five members of the TSSK family from a Banna mini-pig inbred line (BMI) were cloned, sequenced, and characterized. The full-length coding sequences of BMI TSSKs varied from 807 (TSSK3) to 1095 bp (TSSK1) and encoded 268 to 364 amino acids with molecular weights in the range 30.11 to 41.34 kDa. Following comparison with TSSK4 genes in other species, BMI TSSK4 was found to contain three alternatively spliced variants, inform1, inform 3, and inform 4. BMI TSSK1 and TSSK2 are co-localized on the Sus scrofa chromosome (SSC) 14, and consist of a single exon; TSSK3, TSSK4, and TSSK6 are on SSC6, SSC7, and SSC2, and consist of two, four, and one exon, respectively. Multiple protein sequence alignment and phylogenetic analysis showed that the regions spanning the S_TKc domains were more conserved between pig and other animals: with TSSK1 and TSSK2 and TSSK3 and TSSK6 displaying the greatest degree of homology across species, and the TSSK4 protein clearly distinct from other members. Multi-tissue RT-PCR showed BMI TSSK1, TSSK3, and TSSK4 were only expressed in the testes and seminal vesicle, TSSK2 was confined to testes only, while TSSK6 was expressed widely in adult tissues but was highest in the testes.

Differential microRNA expression in signet-ring cell carcinoma compared with tubular adenocarcinoma of human gastric cancer.

Gastric cancer is a disease with a heterogeneous pathology; its pathological mechanisms remain unclear because there is a poor understanding of its etiology. In this study, we identified differentially expressed microRNAs (miRNAs) among various gastric cancer subtypes. miRNA microarray analysis and bioinformatic analysis were used to compare miRNA expression between the signet-ring cell carcinoma and tubular adenocarcinoma subtypes of gastric cancer. Thirteen dysregulated miRNAs were identified in signet-ring cell carcinoma compared with tubular adenocarcinoma: miR-30a, miR-26b, miR-381, let-7i, miR-29c, miR-543, miR-499-3p, miR-628-3p, miR-524-5p, miR-181b, miR-1914, miR-663b, and miR-676. This is the first time that miR-499-3p, miR-628-3p, miR-524-5p, and miR-1914 have been identified in gastric cancer tissues. Bioinformatic analysis using target prediction algorithms indicated that these miRNAs are directly involved in gastric cancer pathogenesis and have different pathological mechanisms in various subtypes of signet-ring cell carcinoma and tubular adenocarcinoma. The miRNA expression patterns in different gastric adenocarcinoma subtypes may help discriminate between signet-ring cell and tubular gland cancer or other gastric cancer subtypes that would otherwise be difficult to identify using routine histological and immunohistochemical analyses. These preliminary data should be verified in further prospective studies.

Isolation, molecular cloning, and characterization of a novel porcine lymphotoxin beta receptor gene.

The lymphotoxin beta receptor (LTßR) is a member of the tumor necrosis factor family of receptors (TNFR). It plays a role in regulating lymphoid organogenesis and homeostasis of the immune system. In the present study, the full coding region of a putative LTßR gene of Sus scrofa was amplified by reverse transcription-polymerase chain reaction (RT-PCR) and cloned for the first time (accession Nos. JX457347 and AFU74012). In addition, analysis of the tissue expression profile was carried out via RT-PCR. The full-length coding region of porcine LTßR had 1266 nucleotides (molecular weight, 45.61 kDa; pI, 5.71) and encoded 421 amino acids. Bioinformatic prediction indicates that LTßR belongs to the TNFR superfamily and contains a TNFR domain. The sequence homology analysis revealed that the amino acid sequences of S. scrofa LTßR had 82.9, 82.4, 81.3, 80.5, 78.7, 74.6, and 73.0% identity with those of Equus caballus, Canis lupus, Ailuropoda melanoleuca, Oryctolagus cuniculus, Bos taurus, Mus musculus, and Homo sapiens, respectively. The phylogenetic tree based on the amino acid sequences of LTßR from 8 species revealed that S. scrofa was more closely related to E. caballus, C. lupus, and A. melanoleuca. RT-PCR analysis showed that the porcine LTßR gene was differentially expressed (e.g., high, moderate, low, or nonexistent) in various tissues (e.g., prostate, pituitary, brainstem, and esophagus, respectively). This may be related to differences in the regulation of LTßR in the different tissues.

Carcass composition and meat quality of indigenous Yanan pigs of China.

The Yanan (YN) pig is a traditional Chinese indigenous breed that is raised in southwest China in the Sichuan Province, but there is little data on the germplasm characteristics of this breed. To evaluate carcass characteristics and meat quality of the YN pig, we compared carcass and meat quality of YN pigs and Landrace × Yanan (CY) hybrid pigs; 30 YN pigs and 30 CY pigs weighing 20 ± 2 kg were reared and slaughtered at the normal slaughter weight (100-120 kg). The carcasses were chilled and the left carcass side was dissected into bone, lean meat, fat, and skin; meat quality parameters were measured. Carcasses of YN pigs were lighter (88.85 vs 90.05 kg, P < 0.05) and shorter (71.88 vs 77.61 cm, P < 0.001); they contained less lean meat (41.60 vs 49.25%, P < 0.001), less ham and breech (25.93 vs 27.53%, P < 0.001) and less carcass bone (9.83 vs 10.53%, P < 0.01) than did carcasses of CY pigs. On the other hand, YN pigs had more carcass subcutaneous fat and skin (48.58 vs 40.23%, P < 0.001), thicker backfat (3.67 vs 3.43 cm, P < 0.001) and smaller loin muscle area (9.83 vs 26.91 cm(2), P < 0.001) compared with CY pigs. Among meat quality parameters, YN pigs had higher pH(1) (6.41 vs 6.17, P < 0.001), higher color score(u) (3.86 vs 3.36, P < 0.001) and lower Minolta L(u) values (40.89 vs 45.32, P < 0.01) than CY pigs. On the other hand, YN pigs had lower drip loss (1.31 vs 2.26%, P < 0.05) and lesser fiber area (2351.34 vs 3025.43 µm(2), P < 0.01) than CY pigs. Both breeds had high intramuscular fat (4.46% in YN and 4.45% in CY). No significant differences in other carcass traits and meat quality were found in the two populations. We conclude that YN pigs could be used in commercial pig production to provide good tasting and high-quality niche products.