The human cumulus--oocyte complex gene-expression profile.
BACKGROUND
The understanding of the mechanisms regulating human oocyte maturation is still rudimentary. We have identified transcripts differentially expressed between immature and mature oocytes and cumulus cells.


METHODS
Using oligonucleotide microarrays, genome-wide gene expression was studied in pooled immature and mature oocytes or cumulus cells from patients who underwent IVF.


RESULTS
In addition to known genes, such as DAZL, BMP15 or GDF9, oocytes up-regulated 1514 genes. We show that PTTG3 and AURKC are respectively the securin and the Aurora kinase preferentially expressed during oocyte meiosis. Strikingly, oocytes overexpressed previously unreported growth factors such as TNFSF13/APRIL, FGF9, FGF14 and IL4 and transcription factors including OTX2, SOX15 and SOX30. Conversely, cumulus cells, in addition to known genes such as LHCGR or BMPR2, overexpressed cell-to-cell signalling genes including TNFSF11/RANKL, numerous complement components, semaphorins (SEMA3A, SEMA6A and SEMA6D) and CD genes such as CD200. We also identified 52 genes progressively increasing during oocyte maturation, including CDC25A and SOCS7.


CONCLUSIONS
The identification of genes that were up- and down-regulated during oocyte maturation greatly improves our understanding of oocyte biology and will provide new markers that signal viable and competent oocytes. Furthermore, genes found expressed in cumulus cells are potential markers of granulosa cell tumours.
Assou
Said
S
CHU Montpellier, Institut de Recherche en Biothérapie, Hôpital Saint-Eloi, and INSERM U 475, Université Montpellier, UFR de Médecine, France.
Anahory
Tal
T
Pantesco
Véronique
V
Le Carrour
Tanguy
T
Pellestor
Franck
F
Klein
Bernard
B
Reyftmann
Lionel
L
Dechaud
Hervé
H
De Vos
John
J
Hamamah
Samir
S
D064108:Aurora Kinase C; D064127:Aurora Kinases; D002352:Carrier Proteins / Q000096:biosynthesis; D015536:Down-Regulation; D005260:Female; D005307:Fertilization in Vitro; D018507:Gene Expression Regulation, Developmental; D006107:Granulosa Cells / Q000502:physiology*; D006133:Growth Substances / Q000096:biosynthesis; D006801:Humans; D008562:Membrane Glycoproteins / Q000096:biosynthesis; D008565:Membrane Proteins / Q000096:biosynthesis; D009363:Neoplasm Proteins / Q000096:biosynthesis; D020411:Oligonucleotide Array Sequence Analysis; D009865:Oocytes / Q000502:physiology*; D017346:Protein Serine-Threonine Kinases / Q000096:biosynthesis; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; D064249:Securin; D039961:Semaphorins / Q000096:biosynthesis; D014157:Transcription Factors / Q000096:biosynthesis; D053300:Tumor Necrosis Factor Ligand Superfamily Member 13; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis; D015854:Up-Regulation
D002352:Carrier Proteins; D006133:Growth Substances; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D009363:Neoplasm Proteins; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; D064249:Securin; D039961:Semaphorins; C505686:TNFRSF11A protein, human; C505688:TNFSF11 protein, human; C114631:TNFSF13 protein, human; D014157:Transcription Factors; D053300:Tumor Necrosis Factor Ligand Superfamily Member 13; D014409:Tumor Necrosis Factor-alpha; C578002:pituitary tumor-transforming protein 1, human; C578003:pituitary tumor-transforming protein 2, human; C576927:AURKC protein, human; D064108:Aurora Kinase C; D064127:Aurora Kinases; D017346:Protein Serine-Threonine Kinases