THRSP Human

What is the genomic structure and location of THRSP in humans?

THRSP (thyroid hormone responsive) maps to chromosome 11 (NC_000011.9) in the region between 77774907 and 77779307 on the plus strand and spans approximately 5.6 kilobases. The gene consists of two exons measuring 481 and 603 bp, with only the smaller exon being translated. The coding region of human mRNA for THRSP contains 438 nucleotides, and the complete mRNA (NM_003251.2) spans 1084 nucleotides .

When analyzing THRSP genomic structure in new experimental settings, researchers should use current genomic alignment tools such as Spidey (mRNA to genomic sequence alignment) to verify exon boundaries, particularly in different tissue types where alternative splicing might occur.

What are the known regulatory mechanisms controlling THRSP expression?

THRSP transcription is regulated through multiple mechanisms:

• Hormonal regulation: Thyroid hormone, insulin, and progestin can induce THRSP expression

• Nutritional factors: Carbohydrate intake (particularly glucose) upregulates THRSP

• Developmental processes: THRSP is induced during adipose tissue differentiation and lactation

• Inhibitory factors: Glucagon and conjugated linoleic acid inhibit THRSP expression

• Insulin signaling pathway: Insulin increases THRSP mRNA expression approximately 5-8 fold after 180-360 minutes of euglycemic hyperinsulinemia through a phosphoinositide 3-kinase (PI3K)-dependent mechanism

When designing experiments to study THRSP regulation, researchers should control for these variables and consider using time-course studies to capture the dynamic regulation patterns.

How does THRSP contribute to lipid metabolism in human cells?

THRSP plays a crucial role in lipid metabolism through several mechanisms:

• It exists as a heterodimer in human cells actively synthesizing lipids

• Its expression pattern parallels that of fatty acid synthase (FASN) in adipose, liver, and mammary tissues

• Inhibition of THRSP via siRNAs or antisense RNAs reduces expression of genes encoding lipid-synthesizing enzymes

• THRSP interference in mesenchymal stem cells significantly reduces lipid droplet formation

• Key regulators of adipogenesis (LPL, FABP4, PLIN1, CIDEC) are downregulated following THRSP silencing

• THRSP appears to regulate endoplasmic reticulum stress and the PPAR signaling pathway, which are closely related to lipid synthesis and metabolism

Research methodologies should incorporate lipidomic analyses alongside gene expression studies to comprehensively assess THRSP's impact on lipid profiles.

What are the evolutionary relationships of THRSP across species?

THRSP is highly conserved across mammalian species with varying degrees of homology:

• Human THRSP shares 99% homology with Pan troglodytes (chimpanzee)

• 91% homology with Macaca mulatta (rhesus macaque)

• 82% homology with Mus musculus (mouse)

• 80% homology with Rattus norvegicus (rat)

• Homologous proteins are also found in cow, chicken, and dog

Three domains are conserved from the ancestral S14-related peptide (Strait 11499, Mig12, S14-related protein) . When conducting comparative studies, researchers should focus on these conserved domains and consider structural modeling approaches to identify functional similarities despite sequence variations.

What experimental techniques are recommended for measuring THRSP expression levels?

Based on current research approaches:

• qPCR: For accurate quantification of THRSP mRNA levels in tissue samples and cell lines

• Western blot: To assess protein expression levels

• Lentiviral transfection: To establish stable cell lines overexpressing THRSP

• shRNA technology: For effective THRSP silencing in functional studies

• Transcriptomic analysis: RNA-seq to identify downstream targets and pathways

• Proteomic analysis: To complement transcriptomic data for comprehensive pathway analysis

For reliable results, researchers should include appropriate housekeeping genes as controls and validate findings using multiple techniques.

How does THRSP silencing affect mitochondrial function and metabolism?

THRSP silencing has significant effects on mitochondrial function and metabolism:

• Transcriptomic analysis of THRSP-silenced adipocytes reveals substantial alterations in mitochondrial functions and lipid metabolism pathways

• Functional assays demonstrate impaired mitochondrial respiration following THRSP silencing

• Fatty acid oxidation is significantly reduced in THRSP-silenced cells

• Lipidomic analysis shows altered sphingolipid metabolism, particularly decreased hexosylceramide concentrations

• Expression levels of enzymes regulating sphingolipid metabolism are affected

• Key genes in lipid droplet generation (LIPE, DGAT1, AGPAT2) are significantly downregulated

Methodological approach: Researchers investigating this relationship should employ comprehensive metabolic phenotyping including:

• Seahorse XF analysis for mitochondrial respiration

• Radioisotope-labeled substrate studies for measuring fatty acid and glucose metabolism

• Integrated transcriptomic and lipidomic analyses

What is the relationship between THRSP expression and cancer progression?

The relationship between THRSP and cancer appears to be tissue-specific:

In hepatocellular carcinoma (HCC):

• THRSP exhibits decreased expression in HCC tissues compared to adjacent healthy tissues

• Patients with lower THRSP protein and mRNA expression demonstrate worse clinical outcomes

• THRSP knockdown increases cell growth, migration, and invasion of HCC cells

• THRSP overexpression exerts anti-tumor effects both in vivo and in vitro

• Mechanistically, THRSP inhibits epithelial-to-mesenchymal transition through the ERK/ZEB1 signaling pathway

In breast cancer:

• Elevated expression of THRSP in human breast tumors correlates with poor prognosis

• Absence of THRSP expression is associated with longer survival

In thyroid carcinoma:

• THRSP has clinical significance, though the exact mechanisms require further investigation

Research methodology: Studies on THRSP in cancer should include:

• Patient-derived xenograft models

• Analysis of large patient cohorts with long-term follow-up

• Pathway validation using multiple inhibitors/activators

• Integration of clinical data with molecular findings

How is THRSP expression affected by insulin resistance in human adipose tissue?

Research demonstrates a significant relationship between insulin sensitivity and THRSP expression:

• THRSP induction by insulin is impaired in insulin-resistant subjects

• THRSP expression correlates closely with whole-body insulin sensitivity measured by euglycemic insulin clamp technique

• In vivo studies show that insulin increases THRSP mRNA expression 5-fold after 180 minutes and 8-fold after 360 minutes of euglycemic hyperinsulinemia

• This regulatory mechanism depends on the phosphoinositide 3-kinase (PI3K) pathway

Experimental approach for researchers:

• Euglycemic insulin clamp paired with adipose tissue biopsies

• In vitro adipocyte models with induced insulin resistance

• Time-course analyses to capture dynamic expression changes

• Pathway inhibitor studies to confirm signaling mechanisms

What multi-omics approaches are most valuable for comprehensive THRSP function analysis?

Integrative multi-omics approaches provide the most comprehensive understanding of THRSP function:

• Combined transcriptomic and proteomic analyses reveal that differential genes/proteins following THRSP interference are enriched in:

  • Lipolytic regulation

  • Endoplasmic reticulum stress

  • Cholesterol metabolism

  • Sphingolipid metabolism

  • PPAR signaling pathway

  • Glycerophospholipid metabolism

• Transcriptomic analysis identifies ATF6 (endoplasmic reticulum stress marker gene) as the most significantly downregulated transcription factor following THRSP interference

• Lipidomic analysis complements these findings by identifying specific lipid species affected by THRSP alterations, such as decreased hexosylceramide concentrations

Recommended methodological framework:

• RNA-seq for comprehensive transcriptome profiling

• Quantitative proteomics using DIA (Data-Independent Acquisition)

• Targeted lipidomics focusing on sphingolipids and glycerophospholipids

• Metabolomics to identify metabolic pathway changes

• Integrative bioinformatics approaches to identify convergent pathways

What experimental models are most appropriate for studying THRSP function in different human tissues?

Different experimental models offer distinct advantages for tissue-specific THRSP research:

For adipose tissue studies:

• Simpson-Golabi-Behmel syndrome (SGBS) adipocytes provide a reliable human adipocyte model

• C3H10 mouse mesenchymal stem cells allow for adipogenic differentiation studies

For liver function studies:

• HCC cell lines with modulated THRSP expression

• Patient-derived liver organoids

For cancer research:

• Patient-derived xenograft models

• 3D tumor spheroid cultures

For systemic metabolic studies:

• Euglycemic insulin clamp with tissue biopsies in human subjects

• Transgenic mouse models with tissue-specific THRSP alterations

How do thyroid hormones and insulin interact to regulate THRSP expression?

The interplay between thyroid hormones and insulin in regulating THRSP expression is complex:

• Both thyroid hormones and insulin independently induce THRSP expression

• Thyroid hormones regulate THRSP via thyroid hormone response elements in the promoter region

• Insulin induces THRSP through the PI3K signaling pathway

• In conditions of insulin resistance, the induction of THRSP by insulin is significantly impaired

• The timing of expression differs: insulin effects are observed within hours, while thyroid hormone effects may take longer

Experimental methodology for investigating this interaction:

• Sequential and combined hormone treatments with time-course analysis

• Chromatin immunoprecipitation (ChIP) to identify binding of thyroid hormone receptors and insulin-responsive transcription factors

• Promoter mutation studies to identify critical regulatory elements

• Studies in models with selective hormone receptor deficiencies

What pathways connect THRSP to endoplasmic reticulum stress response?

Recent evidence suggests important connections between THRSP and endoplasmic reticulum (ER) stress:

• Transcriptomic and proteomic analyses show THRSP interference affects ER stress pathways

• ATF6, a key marker gene for ER stress, is significantly downregulated following THRSP interference

• This relationship may explain how THRSP influences lipid metabolism, as ER stress is closely linked to lipid synthesis and metabolism disorders

• The PPAR signaling pathway, which is affected by THRSP levels, also intersects with ER stress responses

Recommended research approach:

• Monitor expression of key ER stress markers (GRP78, CHOP, XBP1 splicing) following THRSP modulation

• Use specific ER stress inducers (tunicamycin, thapsigargin) with and without THRSP modulation

• Apply proximity ligation assays to identify direct protein interactions

• Measure calcium flux and ER morphology to assess functional consequences