Limits...
Histoplasma capsulatum heat-shock 60 orchestrates the adaptation of the fungus to temperature stress.

Guimarães AJ, Nakayasu ES, Sobreira TJ, Cordero RJ, Nimrichter L, Almeida IC, Nosanchuk JD - PLoS ONE (2011)

Bottom Line: Unique interactions were found at each temperature [30°C (81 proteins), 37°C (14) and 37/40°C (47)].There were fewer unique interactions in cytoplasm [30°C (6), 37°C (25) and 37/40°C (39)] and four common interactions, including additional Hsps and other known virulence factors.These results show the complexity of Hsp60 function and provide insights into Hc biology, which may lead to new avenues for the management of histoplasmosis.

View Article: PubMed Central - PubMed

Affiliation: Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine of Yeshiva University, Bronx, New York, United States of America.

ABSTRACT
Heat shock proteins (Hsps) are among the most widely distributed and evolutionary conserved proteins. Hsps are essential regulators of diverse constitutive metabolic processes and are markedly upregulated during stress. A 62 kDa Hsp (Hsp60) of Histoplasma capsulatum (Hc) is an immunodominant antigen and the major surface ligand to CR3 receptors on macrophages. However little is known about the function of this protein within the fungus. We characterized Hc Hsp60-protein interactions under different temperature to gain insights of its additional functions oncell wall dynamism, heat stress and pathogenesis. We conducted co-immunoprecipitations with antibodies to Hc Hsp60 using cytoplasmic and cell wall extracts. Interacting proteins were identified by shotgun proteomics. For the cell wall, 84 common interactions were identified among the 3 growth conditions, including proteins involved in heat-shock response, sugar and amino acid/protein metabolism and cell signaling. Unique interactions were found at each temperature [30°C (81 proteins), 37°C (14) and 37/40°C (47)]. There were fewer unique interactions in cytoplasm [30°C (6), 37°C (25) and 37/40°C (39)] and four common interactions, including additional Hsps and other known virulence factors. These results show the complexity of Hsp60 function and provide insights into Hc biology, which may lead to new avenues for the management of histoplasmosis.

Show MeSH

Related in: MedlinePlus

Co-immunoprecipitation identifies proteins partners that display distinct patterns in the different cellular fractions and temperature conditions.(A) Representative SDS-PAGE gel of pull down samples obtained after co-immunoprecipitation of extracts. The experiment was repeated three times with consistent results. (B) Immunoblots with mAbs against the H2B, M antigen and Hsp70 indicated the presence of these proteins in the extracts.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3037374&req=5

pone-0014660-g003: Co-immunoprecipitation identifies proteins partners that display distinct patterns in the different cellular fractions and temperature conditions.(A) Representative SDS-PAGE gel of pull down samples obtained after co-immunoprecipitation of extracts. The experiment was repeated three times with consistent results. (B) Immunoblots with mAbs against the H2B, M antigen and Hsp70 indicated the presence of these proteins in the extracts.

Mentions: Protein extracts eluted from agarose beads coated with Hsp60-binding mAb were subjected to SDS-PAGE and silver-stained. In all extracts, several protein bands were observed, ranging from 250 to 10 kDa (Figure 3A). Hsp60 interacted with more proteins in the cell wall extracts than in cytoplasm extracts. However, a distinct pattern of interactions was observed for each temperature when the same cellular compartment was analyzed. Although the number of interacting proteins increased significantly with temperature rise, common bands were observed in the cytoplasm at 37 and 37/40°C. The finding that there were more Hsp60-interacting partners with the cell wall extracts with increasing temperature suggests that the trafficking activity of this protein and localization of several proteins to this organelle is augmented at high temperature stress condition.


Histoplasma capsulatum heat-shock 60 orchestrates the adaptation of the fungus to temperature stress.

Guimarães AJ, Nakayasu ES, Sobreira TJ, Cordero RJ, Nimrichter L, Almeida IC, Nosanchuk JD - PLoS ONE (2011)

Co-immunoprecipitation identifies proteins partners that display distinct patterns in the different cellular fractions and temperature conditions.(A) Representative SDS-PAGE gel of pull down samples obtained after co-immunoprecipitation of extracts. The experiment was repeated three times with consistent results. (B) Immunoblots with mAbs against the H2B, M antigen and Hsp70 indicated the presence of these proteins in the extracts.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3037374&req=5

pone-0014660-g003: Co-immunoprecipitation identifies proteins partners that display distinct patterns in the different cellular fractions and temperature conditions.(A) Representative SDS-PAGE gel of pull down samples obtained after co-immunoprecipitation of extracts. The experiment was repeated three times with consistent results. (B) Immunoblots with mAbs against the H2B, M antigen and Hsp70 indicated the presence of these proteins in the extracts.
Mentions: Protein extracts eluted from agarose beads coated with Hsp60-binding mAb were subjected to SDS-PAGE and silver-stained. In all extracts, several protein bands were observed, ranging from 250 to 10 kDa (Figure 3A). Hsp60 interacted with more proteins in the cell wall extracts than in cytoplasm extracts. However, a distinct pattern of interactions was observed for each temperature when the same cellular compartment was analyzed. Although the number of interacting proteins increased significantly with temperature rise, common bands were observed in the cytoplasm at 37 and 37/40°C. The finding that there were more Hsp60-interacting partners with the cell wall extracts with increasing temperature suggests that the trafficking activity of this protein and localization of several proteins to this organelle is augmented at high temperature stress condition.

Bottom Line: Unique interactions were found at each temperature [30°C (81 proteins), 37°C (14) and 37/40°C (47)].There were fewer unique interactions in cytoplasm [30°C (6), 37°C (25) and 37/40°C (39)] and four common interactions, including additional Hsps and other known virulence factors.These results show the complexity of Hsp60 function and provide insights into Hc biology, which may lead to new avenues for the management of histoplasmosis.

View Article: PubMed Central - PubMed

Affiliation: Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine of Yeshiva University, Bronx, New York, United States of America.

ABSTRACT
Heat shock proteins (Hsps) are among the most widely distributed and evolutionary conserved proteins. Hsps are essential regulators of diverse constitutive metabolic processes and are markedly upregulated during stress. A 62 kDa Hsp (Hsp60) of Histoplasma capsulatum (Hc) is an immunodominant antigen and the major surface ligand to CR3 receptors on macrophages. However little is known about the function of this protein within the fungus. We characterized Hc Hsp60-protein interactions under different temperature to gain insights of its additional functions oncell wall dynamism, heat stress and pathogenesis. We conducted co-immunoprecipitations with antibodies to Hc Hsp60 using cytoplasmic and cell wall extracts. Interacting proteins were identified by shotgun proteomics. For the cell wall, 84 common interactions were identified among the 3 growth conditions, including proteins involved in heat-shock response, sugar and amino acid/protein metabolism and cell signaling. Unique interactions were found at each temperature [30°C (81 proteins), 37°C (14) and 37/40°C (47)]. There were fewer unique interactions in cytoplasm [30°C (6), 37°C (25) and 37/40°C (39)] and four common interactions, including additional Hsps and other known virulence factors. These results show the complexity of Hsp60 function and provide insights into Hc biology, which may lead to new avenues for the management of histoplasmosis.

Show MeSH
Related in: MedlinePlus