HSPB11 produced in E.Coli is a single, non-glycosylated polypeptide chain containing 164 amino acids (1-144 a.a.) and having a molecular mass of 18.5kDa (Molecular weight on SDS-PAGE will appear higher).
HSPB11 is fused to a 20 amino acid His-tag at N-terminus & purified by proprietary chromatographic techniques.
Heat shock protein beta-11, Hspb11, Placental protein 25, PP25, C1orf41, HSPC034, IFT25.
MGSSHHHHHH SSGLVPRGSH MRKIDLCLSS EGSEVILATS SDEKHPPENI IDGNPETFWT TTGMFPQEFI ICFHKHVRIE RLVIQSYFVQ TLKIEKSTSK EPVDFEQWIE KDLVHTEGQL QNEEIVAHDG SATYLRFIIV SAFDHFASVH SVSAEGTVVS NLSS.
HSPB11 (Heat Shock Protein B11) belongs to the HSPB family of small heat shock proteins according to human heat shock protein nomenclature guidelines . It is also known as Intraflagellar transport protein 25 homolog, indicating potential roles in ciliary function . The protein consists of 144 amino acids (M1-S144) and represents an important member of the small heat shock protein family that has gained attention for its roles in various cellular processes .
Based on current research, HSPB11 appears to be involved in multiple cellular processes:
Potential roles in intraflagellar transport (based on its alternative nomenclature)
Involvement in oncogenic processes through E2F targets and KRAS signaling pathways
Immune regulation, particularly affecting Th2 cells and dendritic cells
Research indicates that HSPB11 functions extend beyond typical heat shock protein roles of chaperoning and stress response, with significant implications in disease processes.
HSPB11 demonstrates significantly different expression patterns between normal and diseased tissues, particularly in hepatocellular carcinoma (HCC):
HSPB11 is consistently overexpressed in HCC tumor tissues compared to normal liver tissues
This differential expression shows high discrimination ability between tumor and normal tissues with an area under the ROC curve of 0.923
Expression data validated across multiple databases including TCGA, GTEx, GSE14520, and GSE62232
Validation through qRT-PCR in clinical samples has confirmed these expression differences
These expression patterns suggest HSPB11 may serve as a potential diagnostic marker for certain cancers, particularly HCC.
Researchers investigating HSPB11 expression in clinical contexts should consider these validated methodologies:
Quantitative RT-PCR using validated primers:
Bioinformatic Analysis of public database expression data:
Protein-level validation using:
Western blotting with specific antibodies
Immunohistochemistry on tissue microarrays
Each method requires proper controls and at least three technical replicates per sample for reliable results .
HSPB11 appears to contribute to hepatocellular carcinoma development through multiple mechanisms:
HSPB11-Associated Oncogenic Pathway | Role in Cancer Progression |
---|---|
Cell cycle checkpoints | Dysregulation promotes uncontrolled cell division |
G2M checkpoint | Affects cellular division timing and fidelity |
E2F targets | Influences proliferation-related gene expression |
Rho GTPases signaling | Impacts cellular migration and invasiveness |
KRAS signaling | Promotes sustained proliferative signaling |
Gene Set Enrichment Analysis (GSEA) between HSPB11-high and HSPB11-low patient groups revealed that HSPB11 overexpression significantly alters these oncogenic pathways, potentially explaining its correlation with advanced tumor stage and poorer differentiation .
HSPB11 demonstrates significant associations with tumor immune microenvironment:
Positive correlation with abundance of Th2 cells, which:
Negative association with abundance of dendritic cells (DCs), potentially causing:
These relationships suggest HSPB11 may influence cancer progression not only through direct oncogenic pathways but also by modulating anti-tumor immunity, making it a potential target for immuno-oncology research.
HSPB11 shows significant potential as a prognostic biomarker in HCC based on several clinical correlations:
Researchers can utilize HSPB11 expression data to stratify patients in clinical studies and potentially identify those who might benefit from more aggressive treatment approaches.
Despite promising research findings, several challenges remain in translating HSPB11 research into therapeutics:
Validation requirements:
Mechanistic understanding gaps:
Methodological needs:
Addressing these challenges will require collaborative efforts between basic scientists, clinical researchers, and pharmaceutical developers.
Researchers investigating HSPB11 in disease should consider these bioinformatic approaches:
Differential expression analysis:
Pathway analysis:
Clinical correlation:
Network integration:
These approaches allow for comprehensive characterization of HSPB11's role in disease pathogenesis beyond simple expression differences.
When designing experiments to investigate HSPB11's functional impact, researchers should consider:
Cell line models:
Functional assays:
Signaling pathway validation:
In vivo validation:
Comprehensive experimental design across these platforms will help elucidate HSPB11's functional significance in both normal and disease states.
When encountering contradictory results regarding HSPB11, researchers should:
Assess methodological differences:
Account for tissue and disease heterogeneity:
Apply rigorous statistical approaches:
Integrate multiple data types:
This systematic approach helps resolve apparent contradictions and builds more reliable knowledge about HSPB11 function.
HSP90AB1 is a molecular chaperone that promotes the maturation, structural maintenance, and proper regulation of specific target proteins involved in cell cycle control and signal transduction. It undergoes a functional cycle linked to its ATPase activity, which likely induces conformational changes in client proteins, thereby causing their activation . The protein interacts dynamically with various co-chaperones that modulate its substrate recognition, ATPase cycle, and chaperone function .
HSP90AB1 exhibits low tissue specificity and is expressed in various tissues, including the cerebral cortex, cerebellum, basal ganglia, hypothalamus, midbrain, amygdala, choroid plexus, hippocampal formation, spinal cord, retina, thyroid gland, parathyroid gland, adrenal gland, pituitary gland, lung, salivary gland, esophagus, tongue, stomach, duodenum, small intestine, colon, rectum, liver, gallbladder, pancreas, kidney, urinary bladder, testis, epididymis, seminal vesicle, prostate, vagina, ovary, fallopian tube, endometrium, cervix, placenta, breast, heart muscle, smooth muscle, skeletal muscle, adipose tissue, skin, appendix, spleen, lymph node, tonsil, bone marrow, and thymus .
HSP90AB1 is associated with various diseases, including larynx cancer and bronchitis . It is involved in critical pathways such as SARS-CoV-2 infection and inflammasomes . The protein’s role in gastric apoptosis and inflammation further underscores its importance in cellular homeostasis and disease mechanisms .
Recombinant HSP90AB1 is widely used in research to study its function and interactions with other proteins. It serves as a model to understand the mechanisms of molecular chaperones and their role in maintaining cellular integrity under stress conditions.