WormMine: ExpressionPattern Expr1294

• Pattern: Expression scored from zygote til 50 cell embryo
• Primary Identifier: Expr1294
• Remark: No detailed description for cellular expression pattern at later developmental stages.
• Subcellular Localization: Antibody staining is detectable throughout the cytoplasm and at the periphery of blastomeres up to about the 50-cell stage. The peripheral staining is asymmetric in the cells of the germline lineage P0, P1, P2 and P3. Asymmetric peripheral localization of PAR-6 develops as the newly fertilized egg, P0, progresses through the cell cycle. Localized antibody staining is not detectable in unfertilized mature oocytes, nor in newly fertilized eggs undergoing the first meiotic division. Patchy PAR-6 staining was first detected at the periphery of the embryo after completion of meiosis I, as determined by the presence of a single polar body. 70% of embryos in meiosis II exhibit patchy PAR-6 staining all around the periphery with no obvious asymmetry (n=20). When the female pronucleus completes metaphase II as indicated by the presence of a second polar body, peripheral PAR-6 is restricted to the anterior 85% of embryo length. In embryos between prophase and telophase of the first mitosis, the peripheral PAR-6 is restricted to the anterior 55% EL of the embryos (n=24). During the first cleavage PAR-6 staining is detectable in the advancing furrow. Asymmetry of PAR-6 is also observed in P1 and P2, the germline cells in 2-cell and 4-cell embryos, respectively. Just after the first cleavage, strong peripheral staining is present where P1 apposes AB. The strength of this signal suggests that protein is present along this boundary in both cells. As the P1 cell progressed into prophase, PAR-6 distribution extends posteriorly, covering the anterior 30% of 13 of 16 P1 cells scored. Starting in late metaphase and through anaphase, the distribution of PAR-6 in P1 becomes skewed to the ventrolateral periphery, the part of the cell fated to give rise to EMS. PAR-6 is distributed uniformly at the AB periphery throughout the 2-cell stage. In the 4-cell stage, PAR-6 peripheral staining is strong in ABa, ABp and EMS, but PAR-6 can be detected only faintly around the periphery of P2 until metaphase of P2 at the 7-cell stage. At this time PAR-6 is asymmetrically localized to the dorsal side of P2, the part of the cell fated to give rise to C. The protein is distributed asymmetrically in P3 as well. Peripheral PAR-6 could be detected till about the 50-cell stage.

8 Anatomy Terms

Definition	Name	Synonym	Primary Identifier
Single cell zygote	P0	lineage name: Z	WBbt:0004422
embryonic founder cell	Psub3	lineage name: P0.ppp	WBbt:0006875
embryonic founder cell	Psub1	lineage name: P0.p	WBbt:0006874
embryonic founder cell	Psub2	lineage name: P0.pp	WBbt:0006873
embryonic cell	EMS		WBbt:0006876
embryonic cell	ABa		WBbt:0005906
embryonic cell	ABp		WBbt:0005994
Embryonic founder cell	AB	AB blastomere	WBbt:0004015

1 Genes

WormBase Gene ID	Gene Name	Sequence Name	Organism
WBGene00003921	par-6	T26E3.3	Caenorhabditis elegans

2 Life Stages

Remark	Definition	Other Name	Public Name	Primary Identifier
	The C. elegans life stage spanning 100-290min after first cleavage at 20 Centigrade. Proliferate from 28 cells to 421 cells. Referring to the whole period of gastrulation.		gastrulating embryo Ce	WBls:0000010
	The C. elegans life stage spanning 0-100min after first cleavage at 20 Centigrade. Proliferate from 1 cell to 28 cells. From first cleavage until the start of gastrulation.		blastula embryo Ce	WBls:0000005