IMMUNOGLOBULIN STRUCTURE & DIVERSITY--CHARACTERIZATION OF CELL MEMBRANE PROTEINS

基因进化。编码kappa链亚群成员的基因已经被 从6种不同野鼠产生的重组DNA文库中克隆 物种。这些基因的序列分析目前正在进行中。 这些研究的结果将使多基因进化的评估成为可能 在现代物种形成期间，并提供了对突变机制的见解 为这样的家庭做手术。 增长和监管。浆细胞瘤体外生长所需的一种因子 已经被提纯到明显的同质性。实验目前正在进行中 获得氨基末端序列数据的进展将用于 合成一种用于基因克隆的寡核苷酸探针。尝试次数为 也在进行针对该因子的克隆抗体的研究。 抗体多样性。β(1，6)-半乳聚糖抗体的轻链是 不同寻常的是，它们在VK-JK重组点表达I1e。 这种氨基酸不能由通常位于3‘端的序列产生 VK基因末端或5‘端至JK基因。以确定核苷酸是否 产生这种氨基酸的细菌在重组过程中被编码或添加， 克隆了该可变区的生殖系基因和编码该可变区的cDNA. 已排序。这些研究的结果证实了不寻常的密码子 I1e在胚系中立即3‘到VK的正常终止 编码序列。

Gene evolution. Genes encoding members of a kappa chain subgroup have been cloned from recombinant DNA libraries generated in six different wild mouse species. Sequence analysis of these genes is currently in progress. Results from these studies will permit an assessment of multigene evolution during modern speciation and provide insights into mutational mechanisms operating on such families. Growth and regulation. A factor required for plasmacytoma growth in vitro has been purified to apparent homogeneity. Experiments are currently in progress to obtain amino terminal sequence data which will be used to generate a synthetic oligonucleotide probe for gene cloning. Attempts are also underway to raise monoclonal antibodies to this factor. Antibody diversity. Light chains from antibodies to Beta(1,6)-galactan are unusual in that they express an I1e at the point of VK-JK recombination. This amino acid cannot be generated by sequences usually found at the 3' end of VK genes or 5' to JK genes. To determine whether nucleotides generating this amino acid were germ encoded or added during recombination, the germline gene and cDNA encoding this variable region were cloned and sequenced. Results of these studies confirm that the codon for the unusual I1e is in the germline immediately 3' to the normal termination of the VK coding sequence.