title: A large family of Dscam genes with tandemly arrayed 5' cassettes in Chelicerata.
abstract: Drosophila Dscam1 (Down Syndrome Cell Adhesion Molecules) and vertebrate clustered protocadherins (Pcdhs) are two classic examples of the extraordinary isoform diversity from a single genomic locus. Dscam1 encodes 38,016 distinct isoforms via mutually exclusive splicing in D. melanogaster, while the vertebrate clustered Pcdhs utilize alternative promoters to generate isoform diversity. Here we reveal a shortened Dscam gene family with tandemly arrayed 5' cassettes in Chelicerata. These cassette repeats generally comprise two or four exons, corresponding to variable Immunoglobulin 7 (Ig7) or Ig7-8 domains of Drosophila Dscam1. Furthermore, extraordinary isoform diversity has been generated through a combination of alternating promoter and alternative splicing. These sDscams have a high sequence similarity with Drosophila Dscam1, and share striking organizational resemblance to the 5' variable regions of vertebrate clustered Pcdhs. Hence, our findings have important implications for understanding the functional similarities between Drosophila Dscam1 and vertebrate Pcdhs, and may provide further mechanistic insights into the regulation of isoform diversity.
authors.affiliation: Institute of Biochemistry, Innovation Center for Signaling Network, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang ZJ310058, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Yue
authors.affiliation: College of Life and Environmental Sciences; Hangzhou Normal University, Hangzhou, Zhejiang ZJ310036, China.
authors.forename: Yijun
authors.initials: Y
authors.lastname: Meng
authors.affiliation: Institute of Biochemistry, Innovation Center for Signaling Network, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang ZJ310058, China.
authors.forename: Hongru
authors.initials: H
authors.lastname: Ma
authors.affiliation: Institute of Biochemistry, Innovation Center for Signaling Network, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang ZJ310058, China.
authors.forename: Shouqing
authors.initials: S
authors.lastname: Hou
authors.affiliation: Institute of Biochemistry, Innovation Center for Signaling Network, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang ZJ310058, China.
authors.forename: Guozheng
authors.initials: G
authors.lastname: Cao
authors.affiliation: Institute of Biochemistry, Innovation Center for Signaling Network, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang ZJ310058, China.
authors.forename: Weiling
authors.initials: W
authors.lastname: Hong
authors.affiliation: Institute of Biochemistry, Innovation Center for Signaling Network, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang ZJ310058, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Shi
authors.affiliation: Institute of Biochemistry, Innovation Center for Signaling Network, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang ZJ310058, China.
authors.forename: Pengjuan
authors.initials: P
authors.lastname: Guo
authors.affiliation: Institute of Biochemistry, Innovation Center for Signaling Network, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang ZJ310058, China.
authors.forename: Baoping
authors.initials: B
authors.lastname: Liu
authors.affiliation: Institute of Biochemistry, Innovation Center for Signaling Network, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang ZJ310058, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Shi
authors.affiliation: Institute of Biochemistry, Innovation Center for Signaling Network, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang ZJ310058, China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Institute of Biochemistry, Innovation Center for Signaling Network, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang ZJ310058, China.
authors.forename: Yongfeng
authors.initials: Y
authors.lastname: Jin
mesh_terms: D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D060829:Arthropod Proteins / Q000145:classification / Q000235:genetics*; D001181:Arthropods / Q000145:classification / Q000235:genetics*; D001483:Base Sequence; D015815:Cell Adhesion Molecules / Q000145:classification / Q000235:genetics*; D015870:Gene Expression; D014644:Genetic Variation; D008957:Models, Genetic; D008969:Molecular Sequence Data; D005810:Multigene Family; D010802:Phylogeny; D020033:Protein Isoforms / Q000145:classification / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013045:Species Specificity
chemical_list: D060829:Arthropod Proteins; D015815:Cell Adhesion Molecules; D020033:Protein Isoforms