期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1980
卷号:77
期号:12
页码:7059-7063
DOI:10.1073/pnas.77.12.7059
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:A series of overlapping recombinant clones, which cover the alpha 2 (type I) collagen gene, have been isolated by stepwise screening of two libraries of chicken genomic DNA fragments. The first genomic clone was isolated by using a cloned cDNA containing alpha 2 collagen DNA sequences as hybridization probe. The other clones were obtained by a sequence of screenings using defined fragments of the successive genomic clones as hybridization probes. Several types of experiments indicated that the DNA of these clones are truly overlapping and span 55 kilobase pairs of contiguous DNA sequences in the chicken genome. Sequence analysis of small DNA segments of some of these clones confirm that they contain coding sequences which specify alpha 2 collagen. Electron microscopic analysis of hybrids between type I alpha 2 collagen mRNA and the overlapping genomic clones indicates that the chicken alpha 2 collagen gene has a length of at least 37 kilobases, about 7.4 times longer than the corresponding translatable cytoplasmic mRNA. The coding information for alpha 2 collagen is distributed in more than 50 coding sequences which are interrupted by intervening sequences of various sizes. The structure of the gene implies that the conversion of precursor RNA to mature mRNA for alpha 2 collagen includes at least 50 splicing events.