title: Characterization and comparative analyses of zebrafish intelectins: highly conserved sequences, diversified structures and functions.
abstract: Intelectin family, also called the X-lectin family, is a newly discovered gene family involved in development and innate immunity. However, no research was carried out for this gene family in the model organism zebrafish. Here we present the first characterization of seven zebrafish intelectins (zINTLs) and the first systematic comparative analysis of intelectins from various species in order to provide some clues to the function and evolution of this gene family. We examined the expression patterns of zINTLs in various development stages, normal adults, and Aeromonas salmonicida infected adults. Results showed that zINTL1-3 were highly expressed in one or several adult tissues. zINTL4-7, however, were expressed at quite low levels both in adults and various development stages, and some of them showed relaxation of functional constrains as revealed by K(a)/K(s) calculation. Of the seven zINTLs, zINTL3 was expressed predominantly in the liver and highly up-regulated upon infection, suggesting its important roles in immunity. Based on the characterization of zebrafish intelectins, we then conducted a systematic survey of intelectin members in various species and made comparative analyses. We found out that intelectin family may be a deuterostome specific gene family; and their expression patterns, quaternary structures and glycosylations vary considerably among various species, though their sequences are highly conserved. Moreover, these varied features have evolved multiple times independently in different species, resulting in species-specific protein structures and expression patterns.
authors.affiliation: State Key Laboratory of Biocontrol, Guangdong Province Key Laboratory of Therapeutic Functional Genes, Guangzhou, Guangdong, PR China.
authors.forename: Bin
authors.initials: B
authors.lastname: Lin
authors.forename: Zhen
authors.initials: Z
authors.lastname: Cao
authors.forename: Peng
authors.initials: P
authors.lastname: Su
authors.forename: Haibo
authors.initials: H
authors.lastname: Zhang
authors.forename: Mengzhen
authors.initials: M
authors.lastname: Li
authors.forename: Yiqun
authors.initials: Y
authors.lastname: Lin
authors.forename: Dezhi
authors.initials: D
authors.lastname: Zhao
authors.forename: Yang
authors.initials: Y
authors.lastname: Shen
authors.forename: Chenfeng
authors.initials: C
authors.lastname: Jing
authors.forename: Shangwu
authors.initials: S
authors.lastname: Chen
authors.forename: Anlong
authors.initials: A
authors.lastname: Xu
mesh_terms: D048409:Aeromonas salmonicida / Q000502:physiology; D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D017124:Conserved Sequence; D019143:Evolution, Molecular; D005393:Fish Diseases / Q000276:immunology; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D018507:Gene Expression Regulation, Developmental; D006031:Glycosylation; D016905:Gram-Negative Bacterial Infections / Q000276:immunology / Q000662:veterinary; D006801:Humans; D037102:Lectins / Q000737:chemistry / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism; D008969:Molecular Sequence Data; D010802:Phylogeny; D020836:Protein Structure, Quaternary; D012641:Selection, Genetic; D016415:Sequence Alignment; D015027:Zebrafish / Q000145:classification / Q000235:genetics* / Q000254:growth & development / Q000276:immunology* / Q000382:microbiology
chemical_list: D037102:Lectins