Dynamic restricted expression of the chaperone Hsc70 in early chick development

Abstract

The non-inducible chaperone heat shock cognate 70 kDa (Hsc70) is regulated during development. We now characterize its dynamic expression pattern from gastrulation to early organogenesis. Throughout this developmental period, hsc70 transcripts were largely restricted to neuroectoderm- and mesoderm-derived structures. In stage 10 embryos, Hsc70 protein was expressed in the neural tube with increasing rostrocaudal and decreasing dorsoventral gradients, and in some somite cells. This highly regulated expression of Hsc70 is likely to reflect specific developmental functions, besides its well-characterized role in protein folding.

Monoclonal antibody to novel cell surface epitope on Hsc70 promotes morphogenesis of bile ducts in newborn rat liver

“…It is also plausible that Hsc70 is required for recycling of surface proteins and targets them for proteosomal degradation. Hsc70 has also been implicated in various differentiation and developmental processes (de la Rosa et al 1998;Elefant and Palter 1999;Vega-Nunez et al 1999;Shrivastav et al 2008), a finding consistent with its involvement as an active component of survival and proliferation pathways. As reported here, studies initially designed to label OC.10 expressing cells in situ for cell isolation schemes for lineage analysis demonstrated that binding of MAb OC.10 administered by intrasplenic injection promoted a change in bile duct morphology.…”

Developmental expression of Hsp90, Hsp70 and HSF during morphogenesis in the vetigastropod Haliotis asinina

“…m The mid and late veligers (n) express HasHSF in individual cells distributed throughout the visceral mass, from a central position in the vicinity of the larval retractor muscle (arrow), to the ectodermal cells on the underside of the visceral mass (larger arrow). ap animal pole, e eyespot, f foot, lr larval retractor muscle, m mantle, mi micromeres, p prototroch, pe pretrochal ectoderm, sg shell gland, v velum, ve ventrolateral ectoderm, vm visceral mass, vp vegetal pole, asterisk stomodaeum; dashed lines outline the prototroch sentatives (Ding et al 1993;Rutherford and Lindquist 1998;Sconzo et al 1997;Bishop et al 2002;Sass et al 1996;Lele et al 1999;Vega-Núñez et al 1999;Rubio et al 2002). The dynamic spatial expression patterns of the Hsp isoforms and HSF in H. asinina are compatible with these genes having a role in tissue differentiation and morphogenesis.…”

“…As gastrulation involves both complex movements and a change in cell affinities, Hsps may be involved at a number of points in the regulation, coordination and implementation of these events. Hsps have also been implicated in the formation of the neural tube in mouse and chick (D'Sousa and Brown 1998;Loones et al 2000;Vega-Núñez et al 1999;Rubio et al 2002) and during somitogenesis and muscle formation in fish, chick and mouse (Sass et al 1996;Vanmuylder et al 2002;Vega-Núñez et al 1999). The germ line expresses Hsps and HSF throughout development in Drosophila (Ding et al 1993), Caenorhabditis elegans (Inoue et al 2003) and mouse (Vanmuylder et al 2002), and their continued expression is important to adult fertility.…”

Programmed cell death in the neurulating embryo is prevented by the chaperone heat shock cognate 70

“…We previously described a dynamic, restricted Hsc70 expression pattern in early chick development (Hernández‐Sánchez et al ., 1994; Morales et al ., 1998; Vega‐Núñez et al ., 1999), an observation difficult to reconcile with a general chaperone function essential for protein folding. To further characterize Hsc70 expression in relation with its possible involvement in the prevention of cell death, Hsc70 expression and apoptotic cells were analysed simultaneously by double labelling using anti‐Hsc70 immunofluorescence and TUNEL.…”

“…It includes ten different members identified thus far in humans and 14 in yeast (Taravia et al ., 1996; Rassow et al ., 1997; Luft & Dix, 1999). Heat shock cognate 70 (Hsc70) expression is very dynamic in early chick embryos (Morales et al ., 1998; Vega‐Núñez et al ., 1999), as is the case for many 70 kDa protein family members in different species, revealing complex developmental regulation. Inducible and so‐called constitutive members coexist, both with restricted patterns, as well as alternate phases of inducible or constitutive expression for a single member during development (Luft & Dix, 1999; Loones et al ., 2000).…”