Short communication:: Effects of increased expression of α-lactalbumin in transgenic mice on milk yield and pup growth
Short communication:: Effects of increased expression of α-lactalbumin in transgenic mice on milk yield and pup growth
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DOI：
10.3168/jds.s0022-0302(01)74516-x
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发表时间：
2001-03-01
影响因子：
3.5
通讯作者：
Miller, DJ
中科院分区：
文献类型：
--
作者：
Boston, WS;Bleck, GT;Miller, DJ
乳糖合酶（β1,4-半乳糖基转移酶和 α-乳清蛋白的复合物）在乳腺上皮细胞的高尔基复合体中形成乳糖。为了确定α-乳清蛋白是否是该复合物中的限制成分，对表达牛α-乳清蛋白的转基因小鼠进行了研究。转基因小鼠的乳汁中产生了 0.5 至 1.5 毫克/毫升的牛 α -乳清蛋白，比对照小鼠乳汁中的 α -乳清蛋白多 5 至 15 倍。转基因小鼠和对照小鼠产生的乳汁具有相同浓度的乳糖、奶油和总固体，并且表现出相似的乳腺生长、形态和组织学。转基因小鼠的乳汁中的蛋白质含量比对照小鼠的乳汁少 0.6% (P < 0.05)。 β-乳清蛋白转基因小鼠乳腺匀浆的体外乳糖合酶活性增加（P < 0.05），表明牛β-乳清蛋白可以与鼠β1,4-半乳糖基转移酶相互作用。哺乳期转基因小鼠饲养的幼崽在哺乳期第 10 天的生长速度增加了 4%，表明产奶量增加了 (P = 0.06)。使用称重-哺乳-称重技术估计的乳汁量在转基因小鼠中往往更高（尽管不显着）（P = 0.11）。这些结果表明，增加母鼠中α-乳清蛋白的表达可促进哺乳后代的生长。
Lactose synthase (a complex of beta1,4-galactosyltransferase and alpha -lactalbumin) forms lactose in the Golgi complex of mammary epithelial cells. To determine whether alpha -lactalbumin is a limiting component in this complex, transgenic mice that expressed bovine alpha -lactalbumin were studied. Transgenic mice produced 0.5 to 1.5 mg/ml of bovine alpha -lactalbumin in their milk, 5-to 15-fold more alpha -lactalbumin than in milk of control mice. Transgenic and control mice produced milk with the same concentrations of lactose, cream, and total solids, and showed similar mammary gland growth, morphology, and histology. Milk from transgenic mice had 0.6% less protein than milk from control mice (P < 0.05). The in vitro lactose synthase activity in mammary gland homogenates from -lactalbumin transgenic mice was increased (P < 0.05), demonstrating that bovine -lactalbumin could interact with murine beta 1,4-galactosyltransferase. Pups reared by lactating transgenic mice showed a 4% increase in growth on d 10 of lactation, suggesting that milk production was increased (P = 0.06). Milk volume, estimated using the weigh-suckle-weigh technique, tended to be higher (although not significantly) in transgenic mice (P = 0.11). These results suggest that augmenting alpha -lactalbumin expression in the dam increases the growth of suckling offspring.