Abstract
Little is known about the proteins that direct the highly conserved patterns of spatial genome organisation in fat. Here we report that adipocyte-specific knockout of the gene encoding nuclear envelope protein Tmem120a disrupts fat genome organisation, thus causing a novel lipodystrophy syndrome. Tmem120a deficiency broadly suppresses lipid metabolism pathway gene expression and induces myogenic gene expression by repositioning genes, enhancers and miRNA-encoding loci between the nuclear periphery and interior. Tmem120a-/- mice, particularly females, exhibit a lipodystrophy syndrome similar to human familial partial lipodystrophy FPLD2, with profound insulin resistance and metabolic defects that manifests upon exposure to an obesogenic diet. Interestingly, similar genome organisation defects occurred in cells from FPLD2 patients that harbour nuclear envelope protein laminA mutations. Our data suggest TMEM120A may mediate/instigate novel categories of adipose tissue dysfunction across the adiposity spectrum and provide a new miRNA-based mechanism possibly driving the unexplained muscle hypertrophy in human lipodystrophy.
Competing Interest Statement
The authors have declared no competing interest.
Footnotes
Author e-mail addresses:
Rafal Czapiewski rafal.czapiewski{at}ed.ac.uk
Dzmitry G. Batrakou d.batrakou{at}gmail.com
Jose I. de las Heras J.delasHeras{at}ed.ac.uk
Roderick N. Carter rod.carter{at}ed.ac.uk
Aishwarya Sivakumar s1633133{at}sms.ed.ac.uk
Magdalena Sliwinska madziakorczak7{at}gmail.com
Charles R. Dixon s1581423{at}sms.ed.ac.uk
Shaun Webb swebb1{at}staffmail.ed.ac.uk
Giovanna Lattanzi giovanna.lattanzi{at}cnr.it
Nicholas M. Morton nik.morton{at}ed.ac.uk
Eric C. Schirmer e.schirmer{at}ed.ac.uk
https://data.mendeley.com/datasets/8hgntm9X3w/draft?a=5fef1d20-884f-4237-8686-1ecb1c02e47c