Warner C M, Brownell M S, Rothschild M F
Department of Biology, Northeastern University, Boston, MA 02115.
J Reprod Immunol. 1991 Apr;19(3):303-13. doi: 10.1016/0165-0378(91)90042-o.
A gene has been described, Ped (Preimplantation embryo development), that influences the rate of cleavage of preimplantation mouse embryos. Previous studies of linkage of Ped gene phenotype (fast or slow embryo development) and H-2 haplotype (H-2b or H-2k) in backcross embryos from the C57BL/10Sn and B10.BR congenic strains have shown that the Ped gene is located in the H-2 complex, the major histocompatibility complex (MHC) of the mouse. The present study was undertaken to localize the Ped gene to a particular subregion of the H-2 complex. Analysis of the B6.K1 and B6.K2 congenic strains, which differ at only the Q subregion of the MHC, was undertaken to test whether the Ped gene is located in the Q subregion of the MHC. Qa-2 antigen expression was used as a marker for the Q subregion and fast or slow development was used to assess Ped gene phenotype in backcross embryos generated from the mating of (B6.K1 x B6.K2)F1 and B6.K1 mice. The results showed linkage of Ped gene phenotype and Qa-2 antigen expression, which strongly supports the idea that the Ped gene is located in the Q subregion of the MHC. In a further set of experiments, litter size and weight were investigated in the B6.K1 and B6.K2 mice. Pure line and reciprocal crosses were made using sires and dams of both the B6.K1 and B6.K2 genotypes. Traits measured on pups included birth weight, weaning weight and weight per day of age from birth to weaning. Litter traits measured were number born and weaned and survivability. Sex effects existed for weaning weight and weight gain per day of age. Males gained more and were heavier than female pups (P less than 0.05). Pups whose sire or dam were B6.K2 were significantly (P less than 0.05) heavier at birth than those pups whose sire or dam were B6.K1, and B6.K2 homozygous pups were significantly (P less than 0.001) heavier than all others. Litters whose dams were B6.K2 had significantly more pups at birth (P less than 0.05) than those litters whose dams were B6.K1. Results suggest that pups that are heterozygous or homozygous B6.K2 are more apt to be heavier at birth and be in larger litters suggesting that genes in the Q region of the H-2 complex are advantageous to reproductive performance.
已经描述了一个名为Ped（植入前胚胎发育）的基因，它会影响植入前小鼠胚胎的分裂速度。先前对来自C57BL/10Sn和B10.BR同源品系的回交胚胎中Ped基因表型（胚胎发育快或慢）与H-2单倍型（H-2b或H-2k）的连锁研究表明，Ped基因位于小鼠主要组织相容性复合体（MHC）的H-2复合体中。本研究旨在将Ped基因定位到H-2复合体的特定亚区域。对仅在MHC的Q亚区域存在差异的B6.K1和B6.K2同源品系进行分析，以测试Ped基因是否位于MHC的Q亚区域。将Qa-2抗原表达用作Q亚区域的标记，并使用发育快或慢来评估由（B6.K1×B6.K2）F1与B6.K1小鼠交配产生的回交胚胎中的Ped基因表型。结果显示Ped基因表型与Qa-2抗原表达存在连锁关系，这有力地支持了Ped基因位于MHC的Q亚区域这一观点。在另一组实验中，对B6.K1和B6.K2小鼠的窝仔数和体重进行了研究。使用B6.K1和B6.K2两种基因型的公鼠和母鼠进行纯系和正反交。对幼崽测量的性状包括出生体重、断奶体重以及从出生到断奶的每日龄体重。测量的窝仔性状包括出生和断奶的数量以及存活率。断奶体重和每日龄体重增加存在性别效应。雄性幼崽比雌性幼崽增重更多且体重更重（P小于0.05）。其父亲或母亲为B6.K2的幼崽出生时比其父亲或母亲为B6.K1的幼崽显著更重（P小于0.05），并且B6.K2纯合幼崽比所有其他幼崽显著更重（P小于0.001）。其母亲为B6.K2的窝仔出生时比其母亲为B6.K1的窝仔显著更多（P小于0.05）。结果表明，B6.K2杂合或纯合的幼崽出生时更有可能更重且窝仔数更大，这表明H-2复合体Q区域的基因对繁殖性能有利。
