Biology subjects

Sanchez-Gurmaches, J.

Publications and source records attributed to Sanchez-Gurmaches, J..

3 recordsLinked to original sources

bioRxiv2023

The widely used Ucp1-CreEvdr transgene elicits complex developmental and metabolic phenotypes.

Bacterial artificial chromosome transgenic models, including most Cre-recombinases, enable potent interrogation of gene function in vivo but require rigorous validation as limitations emerge. Due to its high relevance to metabolic studies, we performed comprehensive analysis of the Ucp1-CreEvdr line which is widely used for brown fat research. Hemizygotes exhibited major brown and white fat transcriptomic dysregulation, indicating potential altered tissue function. Ucp1-CreEvdrhomozygotes also show high mortality, growth defects, and craniofacial abnormalities. Mapping the transgene insertion site revealed insertion in chromosome 1 accompanied by large genomic alterations disrupting several genes expressed in a range of tissues. Notably, Ucp1-CreEvdr transgene retains an extra Ucp1 gene copy that may be highly expressed under high thermogenic burden. Our multi-faceted analysis highlights a complex phenotype arising from the presence of the Ucp1-CreEvdr transgene independently of the intended genetic manipulations. Overall, comprehensive validation of transgenic mice is imperative to maximize discovery while mitigating unexpected, off-target effects. HighlightsO_LIHemizygous Ucp1-CreEvdr mice exhibit substantial brown and white fat tissue dysregulation. C_LIO_LIHomozygous Ucp1-CreEvdr mice display high mortality, growth defects, and craniofacial abnormalities. C_LIO_LIThe Ucp1-CreEvdr transgene integration resulted in major genomic disruptions affecting multiple genes. C_LIO_LIThe Ucp1-CreEvdr transgene retains a possibly functional extra Ucp1 copy. C_LI

molecular biology↗

bioRxiv2023

Single cell transcriptomics identifies adipose tissue CD271+ progenitors for enhanced angiogenesis in limb ischemia

Therapeutic angiogenesis using mesenchymal stem/stromal cell grafts have shown modest and controversial effects in preventing amputation for patients with critical limb ischemia. Through single-cell transcriptomic analysis of human tissues, we identified CD271+ progenitors specifically from subcutaneous adipose tissue (AT) as having the most prominent pro-angiogenic gene profile distinct from other stem cell populations. AT-CD271+ progenitors demonstrated robust in vivo angiogenic capacity, over conventional adipose stromal cell grafts, characterized by long-term engraftment, augmented tissue regeneration, and significant recovery of blood flow in a xenograft model of limb ischemia. Mechanistically, the angiogenic capacity of CD271+ progenitors is dependent on functional CD271 and mTOR signaling. Notably, the number and angiogenic capacity of CD271+ progenitors was strikingly reduced in insulin resistant donors. Our study highlights the identification of AT-CD271+ progenitors with in vivo superior efficacy for limb ischemia. Furthermore, we showcase comprehensive single-cell transcriptomics strategies for identification of suitable grafts for cell therapy. HIGHLIGHTSO_LIAdipose tissue stromal cells have a distinct angiogenic gene profile among human cell sources. C_LIO_LICD271+ progenitors in adipose tissue have a prominent angiogenic gene profile. C_LIO_LICD271+ progenitors show superior therapeutic capacities for limb ischemia. C_LIO_LICD271+ progenitors are reduced and functionally impaired in insulin resistant donors. C_LI GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=194 SRC="FIGDIR/small/527726v2_ufig1.gif" ALT="Figure 1"> View larger version (64K): org.highwire.dtl.DTLVardef@1b5e1aorg.highwire.dtl.DTLVardef@bf2c34org.highwire.dtl.DTLVardef@ef0e68org.highwire.dtl.DTLVardef@9aee1f_HPS_FORMAT_FIGEXP M_FIG C_FIG

cell biology↗

bioRxiv2018

Cold-Induced Thermogenesis Increases Acetylation on the Brown Fat Proteome and Metabolome

Stimulating brown adipose tissue (BAT) energy expenditure could be a therapy for obesity and related metabolic diseases. Achieving this requires a systems-level understanding of the biochemical underpinnings of thermogenesis. To identify novel metabolic features of active BAT, we measured protein abundance, protein acetylation, and metabolite levels in BAT isolated from mice living in their thermoneutral zone or in colder environments. We find that the enzymes which synthesize lipids from cytosolic acetyl-coA are among the most robustly increased proteins after cold acclimation, consistent with recent studies highlighting the importance of anabolic de novo lipogenesis in BAT. In addition, many mitochondrial proteins are hyperacetylated by cold acclimation, including several sites on UCP1, which may have functional relevance. Metabolomics analysis further reveals cold-dependent increases to acetylated carnitine and several amino acids. This BAT multi-omics resource highlights widespread proteomic and metabolic changes linked to acetyl-CoA synthesis and utilization that may be useful in unraveling the remarkable metabolic properties of active BAT.

systems biology↗