WormMine: ExpressionPattern Expr8801

• Pattern: The presence of LET-721::GFP was observed during all developmental stages: embryo, larvae and adult. The LET-721::GFP was also expressed in dauer larvae, an alternate larval stage C. elegans enter under stress conditions. Observation of the spatial expression pattern revealed that LET-721 is found in a many of tissues including: pharynx, body wall muscle, hypoderm, intestine and somatic gonad. In addition to these tissues, sex-specific expression was observed in hermaphrodites, which express LET-721::GFP in the spermatheca, while males express LET-721 in the vas deferens.
• Primary Identifier: Expr8801
• Remark: Picture: Fig 2.
• Subcellular Localization: Subcellular localization of LET-721::GFP is not uniformly dispersed throughout each tissue, rather, it is distributed in an intracellular punctate pattern of reporter expression, indicating mitochondrial localization of the LET-721::GFP construct. To verify that the punctate pattern of expression was a consequence of mitochondrial localization, a GFP reporter strain lacking the mitochondrial localization sequence of LET-721 was examined. This transgenic strain contained a promoter::GFP fusion construct, using the same 5 gene-upstream non-coding region as the previous protein fusion (1,343 bp sequence upstream from the start codon of let-721), but lacking the protein coding sequence for let-721. The let-721-promoter::GFP (BC10569) construct drove expression of GFP in the same tissue types as the translational reporter fusion (pharynx, intestines, muscle, hypoderm, unassigned neurons and spermatheca). However, the let-721-promoter::GFP strain did not exhibit the punctate expression associated with mitochondrial localization, but rather a uniform distribution of fluorescence throughout cells with a concentration of signal localizing to the nucleus due to the influence of the 5' nuclear localization sequence. Along with similar intracellular patterns observed by another group's study of a different mitochondrial protein, the punctate pattern of expression is likely a consequence of the LET-721::GFP protein fusion localizing to the mitochondria.

7 Anatomy Terms

Definition	Name	Synonym	Primary Identifier
A chain of very large cuboidal cells forming a wide central lumen in which food arrives from the posterior pharynx, is digested, and from which waste products proceed to the rectum. Intestinal rings form in groups of two and four cells surrounding the common lumen; thus the epithelium is only one cell deep at any point, with neighboring cells firmly secured to their neighbors by apical adherens junctions. These cells have very large nuclei and many large vacuoles, yolk granules, and other inclusions; the latter increase in number and electron density as the animal ages.	intestine	gut	WBbt:0005772
an accordion-like tube that contains sperm and is the site of oocyte fertilization.	spermatheca		WBbt:0005319
Epidermal layer.	hypodermis	epidermis	WBbt:0005733
Longitudinal bands of muscle cells surrounding animal body, with one band running in each quadrant of the body, regulated contraction and relaxation of these muscles cause locomotion.	body wall musculature	body muscle	WBbt:0005813
the feeding organ, a neuro-muscular pump in the head of the animal, used to ingest food, bacteria suspended in liquid, filter them out, grind them up and transport posteriorly into the instestine.	pharynx	esophagus	WBbt:0003681
That portion of the male reproductive tract, through which sperm are delivered to the proctodeum and then the cloaca in the tail. Thus that portion which is distal to the testis, made of a total of 30 cells.	vas deferens	gon_male_vdef	WBbt:0005337
organ producing either sperm or ova.	gonad		WBbt:0005175

1 Genes

WormBase Gene ID	Gene Name	Sequence Name	Organism
WBGene00002855	let-721	C05D11.12	Caenorhabditis elegans

7 Life Stages

Remark	Definition	Other Name	Public Name	Primary Identifier
	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 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
	A third stage larva specialized for dispersal and long term survival.		dauer larva Ce	WBls:0000032
	The whole period of embryogenesis in the nematode Caenorhabditis elegans, from the formation of an egg until hatching.		embryo Ce	WBls:0000003