WormMine: ExpressionPattern Expr4221

• Pattern: HIS-72::GFP displayed a similar expression pattern in almost all larval and adult nuclei , except that intestinal nuclei showed only low levels of expression. In crosses where sperm bearing the YFP::his-72 transgene fertilized wild-type oocytes, fluorescence from embryonic expression was detected at the approximately 26-cell stage (embryos with two E blastomeres).
• Primary Identifier: Expr4221
• Remark: In embryos, HIS-72::GFP can be detected in nuclei at all stages. When fixed nuclei were viewed at high magnification, the most intense HIS-72::GFP and YFP::HIS-72 fluorescence appeared coincident with DAPI-stained DNA at all stages of the cell cycle. For example, mitotic chromosomes coalesce into a characteristic bar-shaped structure at metaphase that displayed high levels of fluorescence. These observations suggest that the tagged H3.3 proteins are incorporated into nucleosomes. To test this possibility in the his-72::gfp strain, authors used a high salt histone extraction method to separate nucleosomes (containing histone octamers) from nonnucleosomal proteins. Extracts from lysed embryonic nuclei were bound to hydroxyapatite and eluted at increasing salt concentrations. Nonnucleosomal proteins are predicted to elute in 0.35 M NaCl, and core histones elute in 2.5 M NaCl. Coomassie blue staining and Western blot analysis using an anti-histone H3 antibody confirmed that C. elegans histones are enriched in the 2.5 M NaCl eluate fractions. The majority of HIS-72::GFP, predicted to be about 42 kDa, stained positively with an anti-GFP antibody in the 2.5 M NaCl eluate fractions, indicating that HIS-72::GFP is incorporated into nucleosomes. The combined results suggest that H3.3 is present in chromatin throughout development.
• Subcellular Localization: Expressed in nuclei.

1 Anatomy Terms

Definition	Name	Synonym	Primary Identifier
a cellular object that consists of subcellular components, expresses genes or functions.	Cell	Cell type	WBbt:0004017

1 Genes

WormBase Gene ID	Gene Name	Sequence Name	Organism
WBGene00001946	his-72	Y49E10.6	Caenorhabditis elegans

6 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 third stage larva. At 25 Centigrade, it ranges 32.5-40 hours after fertilization, 18.5-26 hours after hatch.		L3 larva Ce	WBls:0000035
	The second stage larva. At 25 Centigrade, it ranges 25.5-32.5 hours after fertilization, 11.5-18.5 hours after hatch.		L2 larva Ce	WBls:0000027
	The fourth stage larva. At 25 Centigrade, it ranges 40-49.5 hours after fertilization, 26-35.5 hours after hatch.		L4 larva Ce	WBls:0000038
	The first stage larva. At 25 Centigrade, it ranges 14-25.5 hours after fertilization, 0-11.5 hours after hatch.		L1 larva Ce	WBls:0000024
	The whole period of embryogenesis in the nematode Caenorhabditis elegans, from the formation of an egg until hatching.		embryo Ce	WBls:0000003