Heat shock protein 70 and ATP as partners in cell homeostasis (Review).

Mallouk, Y; Vayssier-Taussat, M; Bonventre, Joseph V.; Polla, B. S.

doi:10.3892/ijmm.4.5.463

Cited by 51 publications

(47 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Furthermore, we showed that full-length BRCA1 was also able to efficiently inhibit CTD phosphorylation in transfected cells, supporting the idea that BRCA1 can inhibit CAK activity in a cellular context. Thus, BRCA1-mediated inhibition of CAK activity might be regulated by ATP levels in vivo and might be of great relevance in situations where ATP levels could be locally or temporally decreased, for example, under conditions of cellular proliferation, apoptosis, or heat shock (36). The apparent competition between BRCA1-C and ATP is consistent with the ability of BRCA1-C to inhibit CAK activity with respect to different substrates in vitro.…”

Section: Discussionsupporting

confidence: 50%

BRCA1 Can Modulate RNA Polymerase II Carboxy-Terminal Domain Phosphorylation Levels

Moisan

Larochelle

Guillemette

et al. 2004

Molecular and Cellular Biology

View full text Add to dashboard Cite

A high incidence of breast and ovarian cancers has been linked to mutations in the BRCA1 gene. BRCA1 has been shown to be involved in both positive and negative regulation of gene activity as well as in numerous other processes such as DNA repair and cell cycle regulation. Since modulation of the RNA polymerase II carboxyterminal domain (CTD) phosphorylation levels could constitute an interface to all these functions, we wanted to directly test the possibility that BRCA1 might regulate the phosphorylation state of the CTD. We have shown that the BRCA1 C-terminal region can negatively modulate phosphorylation levels of the RNA polymerase II CTD by the Cdk-activating kinase (CAK) in vitro. Interestingly, the BRCA1 C-terminal region can directly interact with CAK and inhibit CAK activity by competing with ATP. Finally, we demonstrated that full-length BRCA1 can inhibit CTD phosphorylation when introduced in the BRCA1 ؊/؊ HCC1937 cell line. Our results suggest that BRCA1 could play its ascribed roles, at least in part, by modulating CTD kinase components.The tumor suppressor gene BRCA1 encodes a protein of 1,863 amino acids that can interact with a plethora of factors involved in transcription, DNA repair, cell cycle regulation, apoptosis, genome integrity, and ubiquitination (16). Theses interactions underlie the extensive implication of BRCA1 in crucial processes related to tumorigenesis. However, how it can precisely ensure those functions still remains unclear. It has been suggested that BRCA1 could exert its tumor suppressor functions, particularly in DNA repair and cell cycle regulation, via its transcriptional activity (39, 53). Interestingly, various BRCA1 target genes carry out functions that could largely account for its involvement in DNA repair and cell cycle control. BRCA1 induces the expression of the DNAdamage-responsive genes p21 WAF1/CIP1 (54) and GADD45 (24), the nucleotide excision repair (NER) genes DDB2 and XPC (26), and the cell cycle arrest genes p27 (62) and 14-3-3 (5), while it represses the expression of the cell cycle-promoting gene cyclin B1 (35).Transcriptional activators generally possess a DNA binding domain that binds specific sequences on promoters and an activating region known to interact with general transcription factors, the RNA polII holoenzyme, and chromatin remodeling machines to recruit the transcriptional machinery to a target promoter (34,47). In contrast to those activators, BRCA1 has been shown to bind DNA only in a nonspecific fashion (46, 64) and has been shown to be a component of RNA polII holoenzyme (4, 51). Moreover, we have previously shown that at high concentration, the BRCA1 C-terminal region (amino acids 1528 to 1863) can stimulate transcription in vivo and in vitro without the requirement for a DNA-tethering function (41). That evidence suggests that BRCA1 can stimulate transcription by a mechanism alternative to recruitment, for example, by modulating an enzymatic activity. In vitro transcription assays using a highly purified system have demonstrated that t...

show abstract

Section: Discussionsupporting

confidence: 50%

BRCA1 Can Modulate RNA Polymerase II Carboxy-Terminal Domain Phosphorylation Levels

Moisan

Larochelle

Guillemette

et al. 2004

Molecular and Cellular Biology

View full text Add to dashboard Cite

show abstract

“…Weber and Janz (2001) found that the ability of the juvenile catfish liver to increase HSP70 expression may have protected hepatic cells from apoptosis, and McConkey (1998) supposed that HSP70 appears to protect cells from both necrosis and apoptosis. Therefore increased HSP70 expression may be capable of shifting the response to a large toxic insult from necrosis to apoptosis (McConkey, 1998;Mallouk et al, 1999).…”

Section: Discussionmentioning

confidence: 99%

Effects of pure microcystin-LR on the transcription of immune related genes and heat shock proteins in larval stage of zebrafish (Danio rerio)

Sun

et al. 2009

Aquaculture

View full text Add to dashboard Cite

“…The 70 kDa family of Hsps (HSP70) contains a number of related isoforms, including a constitutively expressed form, Hsc70, and an inducible form, Hsp70 (Tavaria et al, 1996;Kiang and Tsokos, 1998;Mallouk et al, 1999). Although there are few structural or functional differences between the two proteins, they differ in transcriptional regulation (Brown et al, 1993;Kiang and Tsokos, 1998).…”

Section: Introductionmentioning

confidence: 99%

Extracellular Heat Shock Protein 70: A Critical Component for Motoneuron Survival

Robinson¹,

Tidwell²,

Gould³

et al. 2005

J. Neurosci.

111

View full text Add to dashboard Cite

The dependence of developing spinal motoneuron survival on a soluble factor(s) from their target, muscle tissue is well established both in vivo and in vitro. Considering this apparent dependence, we examined whether a specific component of the stress response mediates motoneuron survival in trophic factor-deprived environments. We demonstrate that, although endogenous expression of heat shock protein 70 (HSP70) did not change during trophic factor deprivation, application of e-rhHsp70 (exogenous recombinant human Hsp70) promoted motoneuron survival. Conversely, depletion of HSP70 from chick muscle extract (MEx) potently reduces the survivalpromoting activity of MEx. Additionally, exogenous treatment with or spinal cord overexpression of Hsp70 enhances motoneuron survival in vivo during the period of naturally occurring cell death [programmed cell death (PCD)]. Hindlimb muscle cells and lumbar spinal astrocytes readily secrete HSP70 in vitro, suggesting potential physiological sources of extracellular Hsp70 for motoneurons. However, in contrast to exogenous treatment with or overexpression of Hsp70 in vivo, muscle-targeted injections of this factor in an ex vivo preparation fail to attenuate motoneuron PCD. These data (1) suggest that motoneuron survival requirements may extend beyond classical trophic factors to include HSP70, (2) indicate that the source of this factor is instrumental in determining its trophic function, and (3) may therefore influence therapeutic strategies designed to increase motoneuron Hsp70 signaling during disease or injury.

show abstract

Heat shock protein 70 and ATP as partners in cell homeostasis (Review).

Cited by 51 publications

References 0 publications

BRCA1 Can Modulate RNA Polymerase II Carboxy-Terminal Domain Phosphorylation Levels

BRCA1 Can Modulate RNA Polymerase II Carboxy-Terminal Domain Phosphorylation Levels

Effects of pure microcystin-LR on the transcription of immune related genes and heat shock proteins in larval stage of zebrafish (Danio rerio)

Extracellular Heat Shock Protein 70: A Critical Component for Motoneuron Survival

Contact Info

Product

Resources

About