Identification of germinal disk region derived genes potentially involved in hen fertility.
Despite the regular decrease in fertility observed in hens, especially in "meat" lines, little is known about genes affecting fertility. We used the Affymetrix microarray to search for oocyte genes whose expression would vary in relation to fertility rate in both "laying" and "meat" line hens. We focused on oocyte genes because several of them have been found to be involved in fertility in other species. Based on microarray analysis, 54 and 84 genes were differentially expressed between germinal disc regions (GDR) of F1 maturation stage oocytes from hens exhibiting either high (100%) or low (from 22% to 80%) fertility rate from laying and meat lines respectively. Most of these differentially expressed genes were distributed between "laying" and "meat" lines indicating that mechanisms involved in the decrease in fertility rates in these two cases were independent. Real time RT-PCR performed on the same samples which were used for microarray confirmed in several cases differences in gene expression levels detected by microarray. Moreover the correlations between gene expression levels and fertility rates were evaluated for the 10 most interesting genes at different stages of follicular maturation and early embryo development on individual GDR samples from hens exhibiting different fertility rates. In total, we identified five genes whose expression levels correlated with fertility rate in accordance with findings of microarray analysis and real time RT-PCR: VWC2, CR407412, TAPA, FGL2, and TRAP6. The biological significance of these genes sheds light on potential mechanisms influencing fertility and could provide candidates for fertility markers in the hen.
Elis
Sebastien
S
Physiologie de la Reproduction et des Comportements UMR 6175 INRA, CNRS, Université F. Rabelais de Tours, Haras Nationaux, 37380 Nouzilly, France.
Blesbois
Elisabeth
E
Couty
Isabelle
I
Balzergue
Sandrine
S
Martin-Magniette
Marie-Laure
ML
Batellier
Florence
F
Govoroun
Marina S
MS
D000704:Analysis of Variance; D000822:Animal Husbandry; D000818:Animals; D054239:Blastodisc / Q000196:embryology / Q000502:physiology*; D002642:Chick Embryo; D002645:Chickens / Q000235:genetics* / Q000254:growth & development; D005298:Fertility / Q000235:genetics*; D020869:Gene Expression Profiling / Q000379:methods*; D018507:Gene Expression Regulation, Developmental; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods; D009865:Oocytes / Q000254:growth & development; D015203:Reproducibility of Results; D020133:Reverse Transcriptase Polymerase Chain Reaction