The existence of a family of unusually large and highly diverged hsp70-1ike proteins (the hspll0/SSE family) has recently been described. The 170 kDa glucose regulated stress protein (grpl70) is a retained endoplasmic reticulum glycoprotein that may be involved in immunoglobulin folding and/or assembly. We describe here the cloning of the cDNA for grpl70 and show that it, like hspll0, is a large and highly diverged hsp70-1ike polypeptide which shares specific features with hsp70 (the dnaK family) and the hspll01SSE family, while also differing from both. Grpl70 contains an ATP binding domain and binds ATP, it possesses a carboxyl terminal NDEL sequence, and its mRNA is anoxia inducible.
In recent years, drifting and inundating brown seaweed (
Sargassum horneri
) biomass, called ‘golden tides’, has frequently drifted and accumulated along the southern coastlines of Korea, causing devastating impacts on the local economy and coastal ecosystems. In this study, based on combined analyses of mitochondrial DNA
cox3
gene and seven microsatellites, we investigated the genetic makeup of the floating
S
.
horneri
populations (
N
= 14) in comparison to Korean benthic populations (
N
= 5), and tracked their genetic sources. Given a shared mtDNA haplotype and oceanic circulation systems, the floating populations may have been originated from the southeastern coast of China (e.g. Zhoushan, Zhejiang province). Population structure analyses with microsatellites revealed two distinct genetic clusters, each comprising floating and benthic populations. High levels of inter-population differentiation were detected within Korean benthic samples. The floating populations from the same periods during a 2015–2018 year were genetically more different from one another than those from different periods. These results suggest that the floating populations might be of multiple genetic sources within geographic origin(s). This study will inform management efforts including the development of “
S
.
horneri
blooming forecasting system”, which will assist in mitigating ecological and economic damages on the Korean coastal ecosystems in the future.
The 110 kDa heat shock protein (HSP) (hsp110) has been shown to be a diverged subgroup of the hsp70 family and is one of the major HSPs in mammalian cells [1,2]. In examining the native interactions of hsp110, we observed that it is found to reside in a large molecular complex. Immunoblot analysis and co-immunoprecipitation studies identified two other HSPs as components of this complex, hsc70 and hsp25. When examined in vitro, purified hsp25, hsp70 and hsp110 were observed to spontaneously form a large complex and to directly interact with one another. When luciferase was added to this in vitro system, it was observed to migrate into this chaperone complex following heat shock. Examination of two deletion mutants of hsp110 demonstrated that its peptide-binding domain is required for interaction with hsp25, but not with hsc70. The potential function of the hsp110-hsc70-hsp25 complex is discussed.z 2000 Federation of European Biochemical Societies.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.