Expression pattern of CRYAB and CTGF genes in two pig breeds at different altitudes / [Padrão de expressão dos genes CRYAB e CTGF em duas raças de suínos em altitudes diferentes]

Tibetan pigs are characterized by significant phenotypic differences relative to lowland pigs. Our previous study demonstrated that the genes CRYAB and CTGF were differentially expressed in heart tissues between Tibetan (highland breed) and Yorkshire (lowland breed) pigs, indicating that they might participate in hypoxia adaptation. CRYAB (ɑB-crystallin) and CTGF (connective tissue growth factor) have also been reported to be associated with lung development. However, the expression patterns of CRYAB and CTGF in lung tissues at different altitudes and their genetic characterization are not well understood. In this study, qRT-PCR and western blot of lung tissue revealed higher CRYAB expression levels in highland and middle-highland Tibetan and Yorkshire pigs than in their lowland counterparts. With an increase in altitude, the expression level of CTGF increased in Tibetan pigs, whereas it decreased in Yorkshire pigs. Furthermore, two novel single-nucleotide polymorphism were identified in the 5' flanking region of CRYAB (g.39644482C>T and g.39644132T>C) and CTGF (g.31671748A>G and g.31671773T>G). The polymorphism may partially contribute to the differences in expression levels between groups at the same altitude. These findings provide novel insights into the high-altitude hypoxia adaptations of Tibetan pigs.

Porcos tibetanos são caracterizados por diferenças fenotípicas significativas em relação aos porcos de planície. Nosso estudo anterior demonstrou que os genes CRYAB e CTGF eram expressos diferentemente nos tecidos do coração entre os porcos tibetanos (raça das terras altas) e Yorkshire (raça das terras baixas), indicando que eles poderiam participar da adaptação à hipoxia. CRYAB (ɑB-crystallin) e CTGF (fator de crescimento do tecido conjuntivo) também foram relatados como estando associados ao desenvolvimento pulmonar. Entretanto, os padrões de expressão do CRYAB e CTGF nos tecidos pulmonares em diferentes altitudes e sua caracterização genética não são bem compreendidos. Neste estudo, o qRT-PCR e a mancha ocidental de tecido pulmonar revelou níveis de expressão de CRYAB mais elevados em porcos tibetanos e Yorkshire de altitude e média altitude do que em seus pares de planície. Com um aumento na altitude, o nível de expressão do CTGF aumentou nos porcos tibetanos, enquanto diminuiu nos porcos Yorkshire. Além disso, foram identificados dois novos polimorfismos de um único nucleotídeo na região flanqueadora de CRYAB (g.39644482C>T e g.39644132T>C) e CTGF (g.31671748A>G e g.31671773T>G). O polimorfismo pode contribuir parcialmente com as diferenças nos níveis de expressão entre grupos a uma mesma altitude. Estas descobertas proporcionam novos conhecimentos sobre as adaptações de hipoxia a alta altitude dos porcos tibetanos.

Study on the Efficient Methods for Chicken Eggshell windowing and the Factors Affecting the Hatchability

In order to find out the main factors influenced the hatchability and improve the hatchability of the windowed chicken eggs at stage X, several experiments were made on the basis of the former patent of eggshell windowing methods on equatorial plane, such as cutting and sealing techniques, air cell recovering, laying position immediately after sealing, as well as the injection volumes into the subgerminal cavity of the blastoderm. The result showed that:1) the best sealing material combination was straw powder (SP) and instant glue (IG); 2) there was a highly positive correlation between air cell rate and hatchability; 3) the highest hatchability increased to 71.6% when the eggs were windowed and sealed with IG dropped firstly and then SP sprinkled, finally lay down with the blunt end upward immediately after being sealed; 4) the hatchability was significantly reduced as injection volume (DMEM) was increased (p 0.05 or p 0.01) from 1 µL to 10 1 µL, and the group of injecting 1 µL was the highest (48.4 %). The hatchability and efficiency with such method of windowing, injecting, and sealing was the highest at the present time (more than 30 eggs per hour per person), and it might be broadly used in the fields of avian transgenesis, genetic resources preservation, and embryonic development model of human medicine.(AU)

Study on the Efficient Methods for Chicken Eggshell windowing and the Factors Affecting the Hatchability

In order to find out the main factors influenced the hatchability and improve the hatchability of the windowed chicken eggs at stage X, several experiments were made on the basis of the former patent of eggshell windowing methods on equatorial plane, such as cutting and sealing techniques, air cell recovering, laying position immediately after sealing, as well as the injection volumes into the subgerminal cavity of the blastoderm. The result showed that:1) the best sealing material combination was straw powder (SP) and instant glue (IG); 2) there was a highly positive correlation between air cell rate and hatchability; 3) the highest hatchability increased to 71.6% when the eggs were windowed and sealed with IG dropped firstly and then SP sprinkled, finally lay down with the blunt end upward immediately after being sealed; 4) the hatchability was significantly reduced as injection volume (DMEM) was increased (p 0.05 or p 0.01) from 1 µL to 10 1 µL, and the group of injecting 1 µL was the highest (48.4 %). The hatchability and efficiency with such method of windowing, injecting, and sealing was the highest at the present time (more than 30 eggs per hour per person), and it might be broadly used in the fields of avian transgenesis, genetic resources preservation, and embryonic development model of human medicine.