title: IGFL: A secreted family with conserved cysteine residues and similarities to the IGF superfamily.
abstract: We have discovered a family of small secreted proteins in Homo sapiens and Mus musculus. The IGF-like (IGFL) genes encode proteins of approximately 100 amino acids that contain 11 conserved cysteine residues at fixed positions, including two CC motifs. In H. sapiens, the family is composed of four genes and two pseudogenes that are referred as IGFL1 to IGFL4 and IGFL1P1 and IGFL1P2, respectively. Human IGFL genes are clustered together on chromosome 19 within a 35-kb interval. M. musculus has a single IGFL family member that is located on chromosome 7. Further, evolutionary analysis shows a lack of direct orthology between any of the four human members and the mouse gene. This relationship between the mouse and the human family members suggests that the multiple members in the human complement have arisen from recent duplication events that appear limited to the primate lineage. Structural considerations and sequence comparisons would suggest that IGFL proteins are distantly related to the IGF superfamily of growth factors. IGFL mRNAs display specific expression patterns; they are expressed in fetal tissues, breast, and prostate, and in many cancers as well, and this pattern is consistent with that of the IGF family members.
authors.affiliation: Nuvelo, San Carlos, CA 94070, USA.
authors.forename: Peter
authors.initials: P
authors.lastname: Emtage
authors.forename: Paolo
authors.initials: P
authors.lastname: Vatta
authors.forename: Matthew
authors.initials: M
authors.lastname: Arterburn
authors.forename: Matthew W
authors.initials: MW
authors.lastname: Muller
authors.forename: Emily
authors.initials: E
authors.lastname: Park
authors.forename: Bryan
authors.initials: B
authors.lastname: Boyle
authors.forename: Sophie
authors.initials: S
authors.lastname: Hazell
authors.forename: Renee
authors.initials: R
authors.lastname: Polizotto
authors.forename: Walter D
authors.initials: WD
authors.lastname: Funk
authors.forename: Y Tom
authors.initials: YT
authors.lastname: Tang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002888:Chromosomes, Human, Pair 19; D017124:Conserved Sequence; D003545:Cysteine; D019143:Evolution, Molecular; D005091:Exons; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D005810:Multigene Family; D011544:Pseudogenes; D017386:Sequence Homology, Amino Acid; D013002:Somatomedins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*
chemical_list: D013002:Somatomedins; D003545:Cysteine