Molecular determinants of the meiotic arrests in mammalian oocytes at different stages of maturation

Figures & data

Figure 1. The first meiotic arrest in germinal vesicle (GV) oocytes. Production of cyclic adenosine monophosphate (cAMP) with adenylyl cyclase (ADCY) by granulosa, theca and cumulus cells activates protein kinase A (PKA) that phosphorylates nuclear kinases, myelin transcription factor 1 (MYT1, abbreviated as M1) and G2 checkpoint kinase (WEE1; abbreviated as W1). Thus, cyclin dependent kinase 1 (CDK1) is remained in a phosphorylated state, and maturation promoting factor (MPF) composed of CDK1 and Cyclin B1 (CCNB1) is repressed. To ensure continuity of meiotic arrest, cAMP in the GV oocytes is holded at high levels via inhibiting phosphodiesterase (PDE) activity with the action of cyclic guanosine monophosphate (cGMP). cGMP is generated by mural granulosa and cumulus cells and then transferred though gap junctions (GJs). GPR, G protein-coupled receptor; Gs, G proteins; CSF, Cytostatic factor; CDC25B, Cell division cycle 25B; APC/C, Anaphase promoting complex/cyclosome; NPPC/NPR2, Natriuretic peptide precursor type C/Natriuretic peptide receptor 2; p, Phosphorylation. The GV is depicted by a gray circle at the upper-right site. The green and red arrows represent activation and repression, respectively.

The oocyte in Figure 1 is appearing in an eliptic format. Its original format is in a round format. Please, provide its appearance in a round format as in the word document i have sent a few days ago with e-mail.

Figure 2. The second meiotic arrest in metaphase II (MII) oocytes. Loss of the gap junctions (GJs) on the oolemma due to luteinizing hormone (LH) surge prevents entrance of cyclic adenosine monophosphate (cAMP) into ooplasm. Meanwhile, intracellular cAMP is converted to AMP by the enzyme phosphodiesterase (PDE). The phosphatase cell division cycle 25B (CDC25B) dephosphorylates cyclin dependent kinase 1 (CDK1). Thus, maturation promoting factor (MPF) consisting of CDK1 and Cyclin B1 (CCNB1) passes through the nuclear region. GPR, G protein-coupled receptor; Gs, G proteins; CSF, Cytostatic factor; MYT1, Myelin transcription factor 1; cGMP, Cyclic guanosine monophosphate; PB, First polar body. The metaphase plate is depicted at the upper site. The green and red arrows represent activation and repression, respectively.

The oocyte in this figure should also be in a round format as in the word document i have sent in the last e-mail. Please, provide the oocyte in a round format, not in an eliptic format.

Table 1. The potential factors leading to permanent meiotic arrests in mammalian germinal vesicle (GV) and metaphase II (MII) oocytes. ND, Not detected. The full names of all abbreviations were given in the text

Arrest stage	Lack of gene	Gene mutation	Down-regulation	Up-regulation	Inhibition	ART application	Chemical	Other factors
GV oocyte	Cdc25b Pde3a Ubb Marf1 Ccnb1/Ccnb2	PATL2	Ccno Plk4 Chk2 Orf1p Gdf9 Bmp15	ND	PDE3 CDK1 PLK1 Transcription Protein synthesis Hyaluronan synthesis	Mineral oil FSH/LH Ovarian stimulation	Caffeine Metformin Thiamethoxam	Absence of Ca^+2 channels DSBs Amino acid level
MI oocyte	Mlh1 Mlh3 Cks2 Mei1 Fmn2 Ccnb3	PATL2 TRIP13 TUBB8	H1foo Spindly Erk3 Syt1 Cep55 Ccnb3 Rasd1 Stau2 Chk1 Prkar2b Survivin Pkcβ1 Fbxo30 Mat2b	Ccnb1 Obox4 BubR1 Chk1 Orf1p Mad2 MPF Spc25 Survivin SPIN1	p38 MAPK CHK2 EZH2 PLD2 PAFAH1B3	Ovarian stimulation	Bisphenol A Thiamethoxam Doxorubicin Diethylstilbestrol Benzo[a]pyrene Nocodazole Cytochalasin		DNA damage Zinc deficiency SAC activation
MII oocyte	ND	ND	Emi2 Gas6	Ccnb1 Obox4 Spin1 UBE2S GPR3 EMI2	ND	ND	Paclitaxel	ND