Bruisten S M, Demant P
Division of Molecular Genetics, Netherlands Cancer Institute (Antoni van Leeuwenhoekhuis), Amsterdam.
Immunogenetics. 1989;29(1):6-13. doi: 10.1007/BF02341607.
C4 (the fourth complement component) and Slp (sexlimited protein) are two homologous plasma proteins encoded by genes in the S-region of the H-2 gene complex. We studied the genetic factors influencing the plasma levels of these proteins and their mRNA levels in liver. Considerable differences in both protein and mRNA levels were found between mouse strains carrying the same S-region allele on different genetic backgrounds, indicating a pretranslational effect of non-H-2-linked genes on the expression of the two S-region genes. The expression of Slp is androgen-dependent in the strains tested. However, testosterone treatment cannot increase the low levels of Slp caused by non-H-2-linked regulatory genes. In mice with Slp-negative S-region alleles we found liver mRNA hybridizing with Slp-specific oligonucleotides, indicating expression of the Slp gene in Slp-negative strains. Our data demonstrate the complexity of the regulation of the C4 and Slp genes and pave the way for the analysis of the regulatory factors involved.
C4（第四补体成分）和性限制蛋白（Slp）是由H-2基因复合体S区域中的基因编码的两种同源血浆蛋白。我们研究了影响这些蛋白血浆水平及其在肝脏中mRNA水平的遗传因素。在不同遗传背景下携带相同S区域等位基因的小鼠品系之间，蛋白和mRNA水平均存在显著差异，这表明非H-2连锁基因对两个S区域基因的表达具有转录前效应。在所测试的品系中，Slp的表达是雄激素依赖性的。然而，睾酮处理并不能增加由非H-2连锁调节基因导致的低水平Slp。在具有Slp阴性S区域等位基因的小鼠中，我们发现肝脏mRNA与Slp特异性寡核苷酸杂交，这表明Slp基因在Slp阴性品系中表达。我们的数据证明了C4和Slp基因调控的复杂性，并为分析其中涉及的调控因子铺平了道路。
