RT info:eu-repo/semantics/article
T1 Phylogeny and regulation of four lipocalin genes clustered in the chicken genome: evidence of a functional diversification after gene duplication
A1 Pagano, Aldo
A1 Giannoni, Paolo
A1 Zambotti, Adriana
A1 Sánchez Romero, Diego
A1 Ganfornina Álvarez, María Dolores
A1 Gutiérrez, Gabriel
A1 Randazzo, Nadia
A1 Cancedda, Ranieri
A1 Dozin, Beatrice
K1 Lipocainas
K1 Proteinas
K1 Genética
AB A novel lipocalin gene is here reported that represents the fourth member of a cluster we have identified in the chicken genome. Thiscluster also includes Chondrogenesis-Associated Lipocalins h and g (CALh, CALg) and Extracellular Fatty Acid Binding Protein (Ex-FABP). The new gene codes for a 22-kDa secreted protein with three cysteine residues and a series of sequence features well conserved in thelipocalin family. All the genes in the cluster are structurally similar presenting comparable exon/intron boundary positions and exon sizes. Aphylogenetic analysis indicates the monophyletic grouping of these genes, and their relationship with the lipocalins a-1-microglobulin(A1mg), complement factor 8g chain (C8GC), prostaglandin D synthase (PGDS), and neutrophil-gelatinase-associated lipocalin (NGAL).The new cluster gene appears to be the ortholog of the mammalian C8GC and was thus named Ggal-C8GC. This orthology also suggests thatthis lipocalin was present in the ancestor common to reptiles and mammals.In addition to other expressing tissues, Ex-FABP, CALh and CALg genes are highly transcribed in chondrocytes at late stages ofchondrogenesis during endochondral bone formation and/or upon inflammatory stimulation. Here, we show that they are alsotranscriptionally induced when chondrocytes are subjected to various biological events as cell quiescence, cell shape transition, and hormonalstimulation. By contrast, Ggal-C8GC transcripts are only barely detectable in chondrocytes, but are more abundant in liver, kidney, brain,heart, skeletal muscle and particularly in skin. Moreover, no expression induction was observed neither during chondrocyte differentiation,nor upon any of the stimulations mentioned above. This indicates that the Ggal-C8GC gene was co-opted for a novel function after theduplication events that gave rise to the cluster.The peculiar coordinated regulation of Ex-FABP, CALh and CALg, and the apparent divergent role of Ggal-C8GC suggest that thesegene duplications may have been maintained during evolution by a sub-functionalization mechanism where some common function(s) areshared by several members of the cluster and some other specialized function(s) are unique to other members.
PB Elsevier
SN 0378-1119
YR 2004
FD 2004
LK http://uvadoc.uva.es/handle/10324/6081
UL http://uvadoc.uva.es/handle/10324/6081
LA eng
NO Gene, 2004, vol. 331, p. 95-106
NO Producción Científica
DS UVaDOC
RD 27-dic-2024