Cell division: first embryonic mitosis (WP1411)

Caenorhabditis elegans

"Prior to fertilization, C. elegans oocytes are arrested in meiotic prophase with nuclei containing two copies of the diploid genome packaged into recombined bivalent chromosomes. The two rounds of meiotic chromosome segregation that generate the haploid oocyte pronucleus are completed in the zygote after the oocytes are fertilized. During each meiotic division, chromosome segregation is accomplished by a small acentriolar meiotic spindle that forms in the embryo anterior. During anaphase of meiosis I and again in meiosis II, the meiotic spindle associates with the cortex in an end-on fashion, and a highly asymmetric cytokinesis-like event extrudes a polar body (Figure 2; Albertson and Thomson, 1993; Clark-Maguire and Mains, 1994; Yang et al., 2003). In addition to the haploid pronucleus, the sperm brings a pair of centrioles into the oocyte, which lacks centrioles due to their degradation during oogenesis. As meiosis completes, the haploid oocyte and sperm-derived pronuclei, located at opposite ends of the embryo increase in size, becoming visible by DIC microscopy. After entering the oocyte, the sperm-derived centriole pair recruits pericentriolar material and acquires the ability to nucleate microtubules (O'Connell, 2000; Pelletier et al., 2004). Subsequently, the two sperm-derived centrioles separate, forming two centrosomes positioned on either side of the paternal pronucleus. Coincident with chromosome condensation during mitotic prophase, the pronuclei migrate towards each other. After the pronuclei meet, the nuclear-centrosome complex moves to the center of the embryo and rotates to align with the long axis of the embryo (Albertson, 1984; Hyman and White, 1987). The miotitc spindle begins to move towards the embryo posterior during metaphase (Labbe et al., 2004; Oegema et al., 2001), and asymmetric elongation during anaphase contributes to its posterior displacement (Albertson, 1984; Grill et al., 2001). Since the cleavage furrow bisects the mitotic spindle, this displacement results in an asymmetric first cleavage (For more on the mechanisms that generate this asymmetry see Asymmetric cell division and axis formation in the embryo). " From "Cell division" by Karen Oegema, WormBook


Karen Yook , Kristina Hanspers , Martina Summer-Kutmon , Egon Willighagen , Alex Pico , Eric Weitz , and Stefan Raats


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Caenorhabditis elegans




Cell Type Ontology

animal zygote animal cell

Pathway Ontology

pathway pertinent to DNA replication and repair, cell cycle, maintenance of genomic integrity, RNA and protein biosynthesis


Label Type Compact Identifier Comment
SCC-1 GeneProduct wormbase:F10G7.4
PLL-1 GeneProduct wormbase:K10F12.3
ZYG-1 GeneProduct wormbase:F59E12.2
T13E8.2 GeneProduct wormbase:T13E8.2
T13E8.3 GeneProduct wormbase:T13E8.3
SPD-5 GeneProduct wormbase:F56A3.4
ANC-1 GeneProduct wormbase:ZK973.6
TBA-1 GeneProduct wormbase:F26E4.8
UNC-60A GeneProduct wormbase:C38C3.5
DYRB-1 GeneProduct wormbase:T24H10.6
CYK-1 GeneProduct wormbase:F11H8.4
TBB-1 GeneProduct wormbase:K01G5.7
TAC-1 GeneProduct wormbase:Y54E2A.3
Y71F9AL.14 GeneProduct wormbase:Y71F9AL.14
AIR-1 GeneProduct wormbase:K07C11.2
DLC-1 GeneProduct wormbase:T26A5.9
MEL-11 GeneProduct wormbase:C06C3.1
MIX-1 GeneProduct wormbase:M106.1
Y19D2B.1 GeneProduct wormbase:Y19D2B.1
SAN-1 GeneProduct wormbase:ZC328.4
SMC-3 GeneProduct wormbase:Y47D3A.26
AIR-2 GeneProduct wormbase:B0207.4
UNC-83 GeneProduct wormbase:W01A11.3
DNC-1 GeneProduct wormbase:ZK593.5
MFDF-1 GeneProduct wormbase:C50F4.11
HIM-1 GeneProduct wormbase:F28B3.7
TBA-4 GeneProduct wormbase:F44F4.11
CLASP GeneProduct wormbase:R107.6
ICP-1/CeINCEP GeneProduct wormbase:Y39G10AR.13
SPD-1 GeneProduct wormbase:Y34D9A.4
IMA-2 GeneProduct wormbase:F26B1.3 GO:0007084
NDC-80 GeneProduct wormbase:W01B6.9
LIS-1 GeneProduct wormbase:T03F6.5
NUD-1 GeneProduct ensembl:WBGene00003829
TAC-1 GeneProduct wormbase:Y54E2A.3
LET-754 GeneProduct wormbase:C29E4.8
Matefin/SUN-1 GeneProduct wormbase:F57B1.2
ZYG-12 GeneProduct wormbase:ZK546.1
CeCENP-C GeneProduct wormbase:T03F1.9
PFD-2 GeneProduct wormbase:H20J04.5
Ce-BAF-1 GeneProduct wormbase:B0464.7
KBP-1 GeneProduct wormbase:Y92C3B.1
TIM-1 GeneProduct wormbase:Y75B8A.22
KNL-3 GeneProduct wormbase:T10B5.6
F54B3.3 GeneProduct wormbase:F54B3.3
PFD-3 GeneProduct wormbase:T06G6.9
Y47D3A.29 GeneProduct wormbase:Y47D3A.29
PLK-2 GeneProduct wormbase:C14B9.4 GO:0000003 GO:0000003 GO:0007077 GO:0000910 GO:0009792 GO:0008340 GO:0051301 GO:0040035 GO:0040038 GO:0051726 GO:0002119 GO:0045132
MIS-12 GeneProduct wormbase:Y47G6A.24
T16G12.1 GeneProduct wormbase:T16G12.1
GPB-1 GeneProduct wormbase:F13D12.7
ZEN-4 GeneProduct wormbase:M03D4.1 GO:0035046 GO:0031991 GO:0051301 GO:0000910 GO:0040038 GO:0009792 GO:0051256
BIR-1 GeneProduct wormbase:T27F2.3
ANI-1 GeneProduct wormbase:Y49E10.19
AIR-1 GeneProduct wormbase:K07C11.2
CYK-1 GeneProduct wormbase:F11H8.4 GO:0000003
NUD-1 GeneProduct ensembl:WBGene00003829
BIR-1 GeneProduct wormbase:T27F2.3
ZYG-9 GeneProduct wormbase:F22B5.7
DNC-1 GeneProduct wormbase:ZK593.5
ROD-1 GeneProduct wormbase:F55G1.4
Ce-emerin/EMR-1 GeneProduct wormbase:M01D7.6
g-tubulin/TBG-1 GeneProduct wormbase:F58A4.8
LRG-1 GeneProduct wormbase:F55H2.4
CeMCAK GeneProduct wormbase:K11D9.1
MDF-2 GeneProduct wormbase:Y69A2AR.30
ARP-1 GeneProduct wormbase:Y53F4B.22 GO:0002009
LIS-1 GeneProduct wormbase:T03F6.5
CSC-1 GeneProduct wormbase:Y48E1B.12
DYCI-1 GeneProduct wormbase:C17H12.1
SAS-6 GeneProduct wormbase:Y45F10D.9
LET-99 GeneProduct wormbase:K08E7.3
TBA-2 GeneProduct wormbase:C47B2.3
BUB-3 GeneProduct wormbase:Y54G9A.6
TAG-170 GeneProduct wormbase:C05D11.3
ANI-1 GeneProduct wormbase:Y49E10.19 GO:0040002 GO:0030865 GO:0009792
KBP-1 GeneProduct wormbase:R13F6.1
21ur-13952 GeneProduct wormbase:C36E8.9 C36E8.9
HCP-6 GeneProduct wormbase:Y110A7A.1
KBP-5 GeneProduct wormbase:C34B2.2
Spc25/KBP-3 GeneProduct wormbase:F26H11.1
RHO-1 GeneProduct wormbase:Y51H4A.3
ICP-1/CeINCENP GeneProduct wormbase:Y39G10AR.13
UNC-59 GeneProduct wormbase:W09C5.2
LET-92 GeneProduct wormbase:F38H4.9
DNC-4 GeneProduct wormbase:C26B2.1
CeCENP-A GeneProduct wormbase:F58A4.3
AIR-2 GeneProduct wormbase:B0207.4
21ur-15150 GeneProduct wormbase:K10D11.8 GO:0035046 GO:0051301 GO:0000910
ZYG-9 GeneProduct wormbase:F22B5.7
RBX-1 GeneProduct wormbase:ZK287.5
CAP-G GeneProduct wormbase:F55C5.4
CAP-2 GeneProduct wormbase:M106.5 GO:0000578
CYK-4 GeneProduct wormbase:K08E3.6 GO:0000003 GO:0000003 GO:0002009 GO:0000910 GO:0007109 GO:0009792 GO:0000281 GO:0051301 GO:0040011 GO:0040035 GO:0010171 GO:0040038
Ce-MAN1/LEM-2 GeneProduct wormbase:W01G7.5
PFD-5 GeneProduct wormbase:R151.9
SPD-5 GeneProduct wormbase:F56A3.4
BEN-1 GeneProduct wormbase:C54C6.2 GO:0035046
DLI-1 GeneProduct wormbase:C39E9.14
ZYG-12 GeneProduct wormbase:ZK546.1
KBP-2 GeneProduct wormbase:F26F4.13
LET-21/Ect-2 GeneProduct wormbase:T19E10.1
SAS-5 GeneProduct wormbase:F35B12.5
HCP-2 GeneProduct wormbase:T06E4.1
KLE-2 GeneProduct wormbase:C29E4.2
CYK-4 GeneProduct wormbase:K08E3.6
GPC-2 GeneProduct wormbase:F08B6.2
HCP-1 GeneProduct wormbase:ZK1055.1
SPD-2 GeneProduct wormbase:F32H2.3
BUB-1 GeneProduct wormbase:R06C7.8
nuf-2/HIM-10 GeneProduct wormbase:R12B2.4
CZW-1 GeneProduct wormbase:F20D12.4
DHC-1 GeneProduct wormbase:T21E12.4
DNC-2 GeneProduct wormbase:C28H8.12
PFN-1 GeneProduct wormbase:Y18D10A.20
PLK-1 GeneProduct wormbase:C14B9.4 GO:0000003 GO:0000003 GO:0007077 GO:0000910 GO:0009792 GO:0008340 GO:0051301 GO:0040035 GO:0040038 GO:0051726 GO:0002119 GO:0045132
LET-502 GeneProduct wormbase:C10H11.9
T26A5.8 GeneProduct wormbase:T26A5.8
TBB-2 GeneProduct wormbase:C36E8.5
ZEN-4 GeneProduct wormbase:M03D4.1
SAS-4 GeneProduct wormbase:F10E9.8
NMY-2 GeneProduct wormbase:F20G4.3
BIR-1 GeneProduct wormbase:T27F2.3
CeGrip-1/GIP-1 GeneProduct wormbase:H04J21.3
SCC-3 GeneProduct wormbase:F18E2.3
KLP-19 GeneProduct wormbase:Y43F4B.6
UNC-84 GeneProduct wormbase:F54B11.3
DNC-2 GeneProduct wormbase:C28H8.12
UNC-61 GeneProduct wormbase:Y50E8A.4
SMC-4 GeneProduct wormbase:F35G12.8
KNL-2 GeneProduct wormbase:K06A5.4
SPD-2 GeneProduct wormbase:F32H2.3
MLC-4 GeneProduct wormbase:C56G7.1
CUL-3 GeneProduct wormbase:Y108G3AL.1 GO:0035046
PUF-3 GeneProduct wormbase:Y45F10A.2
CeLamin/LMN-1 GeneProduct wormbase:DY3.2
MEL-28 GeneProduct wormbase:C38D4.3
CeGrip-2/GIP-2 GeneProduct wormbase:C45G3.3
MBK-2 GeneProduct wormbase:F49E11.1
SPD-5 GeneProduct wormbase:F56A3.4
PAR-5 GeneProduct wormbase:M117.2
UNC-37 GeneProduct wormbase:W02D3.9
KNL-1 GeneProduct wormbase:C02F5.1


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