WormMine: ExpressionPattern Expr2436

• Pattern: Affinity-purified antibodies to IMA-2 detected the protein only in germ line cells. In embryos the maternal IMA-2 was diluted during early cell divisions and was expressed at detectable levels only in the germ line precursor cells Z2 and Z3, not in the somatic cells. In the adult hermaphrodite germ line, IMA-2 was present within all germ cells from the distal end of the germ line to the proximal oocyte. IMA-2 was not detected in sperm.
• Primary Identifier: Expr2436
• Subcellular Localization: In distal germ cells, IMA-2 was predominantly cytoplasmic and NE associated. However, in the developing oocytes IMA-2 was predominantly cytoplasmic and intranuclear with no apparent enrichment at the NE. When distal germ cells in prometaphase and metaphase were evident by DAPI staining of the DNA, IMA-2 was enriched at the region immediately surrounding the condensed chromosomes. In the fertilized egg before pronuclear migration, IMA-2 was predominantly cytoplasmic and NE associated in both pronuclei. The intranuclear IMA-2 in the proximal oocyte had dispersed into the oocyte cytoplasm at NE breakdown, but returned to the NE upon NE reformation around the pronuclei. Because sperm do not contain IMA-2, the male pronuclear IMA-2 must have originated in the egg cytoplasm. As the pronuclei became associated, the intensity of IMA-2 staining at the NE decreased. After pronuclear fusion, IMA-2 completely filled the space surrounding the chromosomes but did not seem to be enriched on the surface of the condensed chromosome. This perichromosomal localization persisted during congression of the chromosomes toward the metaphase plate but had decreased by the time of metaphase plate formation. Early in anaphase as chromosome separation first became apparent, IMA-2 staining could still be seen in the region surrounding the chromosome, but was significantly decreased compared with earlier stages. Later in telophase, IMA-2 again became associated with the NE as soon as the structure was detectable around the daughter nuclei. IMA-2 staining persisted at the NE through cytokinesis and into interphase of the next cell cycle. The mitotic IMA-2 staining was not coincident with beta-tubulin staining in the spindle microtubules or the spindle poles. In two-cell embryos: IMA-2 surrounded the chromosomes only in nuclei that were in late prometaphase or later. Nuclei containing fully condensed chromosomes, but in which the microtubules had not penetrated, excluded IMA-2. Note, however, that by this point IMA-2 was only weakly detected at the NE. Nuclei in which peripheral nucleoporin staining could be detected did not accumulate IMA-2 around the chromosomes.

3 Anatomy Terms

Definition	Name	Synonym	Primary Identifier
cell line which early in development becomes differentiated from the remaining somatic cell line, and alone has the potential to undergo meiosis and form gametes.	germ line	germline	WBbt:0005784
Germ line precursor cell	Z3	lineage name: P4.a	WBbt:0004575
Germ line precursor cell	Z2	lineage name: P4.p	WBbt:0004576

1 Genes

WormBase Gene ID	Gene Name	Sequence Name	Organism
WBGene00002073	ima-2	F26B1.3	Caenorhabditis elegans

2 Life Stages

Remark	Definition	Other Name	Public Name	Primary Identifier
	The stage that begins when a C.elegans individual is fully-developed and has reached maturity.		adult Ce	WBls:0000041
	The whole period of embryogenesis in the nematode Caenorhabditis elegans, from the formation of an egg until hatching.		embryo Ce	WBls:0000003