ATP-binding cassette transporter D2 (D2) is an ABC half transporter that is thought to promote the transport of very long-chain fatty acyl-CoAs into peroxisomes. Both D2 and peroxisomes increase during adipogenesis. Although peroxisomes are essential to both catabolic and anabolic lipid metabolism, their function, and that of D2, in adipose tissues remain largely unknown. Here, we investigated the D2 localization and the proteome of D2-containing organelles, in adipose tissue. Centrifugation of mouse adipose homogenates generated a fraction enriched with D2, but deficient in peroxisome markers including catalase, PEX19, and ABCD3 (D3). Electron microscopic imaging of this fraction confirmed the presence of D2 protein on an organelle with a dense matrix and a diameter of ∼200 nm, the typical structure and size of a microperoxisome. D2 and PEX19 antibodies recognized distinct structures in mouse adipose. Immunoisolation of the D2-containing compartment confirmed the scarcity of PEX19 and proteomic profiling revealed the presence of proteins associated with peroxisome, endoplasmic reticulum (ER), and mitochondria. D2 is localized to a distinct class of peroxisomes that lack many peroxisome proteins, and may associate physically with mitochondria and the ER.
|Number of pages||6|
|Journal||Biochemical and Biophysical Research Communications|
|State||Published - Jan 2 2015|
Bibliographical noteFunding Information:
This work was funded by grants from the National Institute of Diabetes and Digestive and Kidney Diseases (Grant DK080874 , DK100892 ). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. We acknowledge the University of Kentucky Proteomics Core that is partially supported by grants from the National Cancer Institute ( P30CA177558 ) and the National Institute of General Medical Sciences ( P20GM103486 ) from the National Institutes of Health . The authors would like to acknowledge Jeannie Haak for assistance with manuscript preparation.
© 2014 Elsevier Inc. All rights reserved.
- ABC transporter
- Adipose tissue
- Subcellular organelle
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology