Transcript profiling and lipidomic analysis of ceramide subspecies in mouse embryonic stem cells and embryoid bodies.
Ceramides (Cers) are important in embryogenesis, but no comprehensive analysis of gene expression for Cer metabolism nor the Cer amounts and subspecies has been conducted with an often used model: mouse embryonic stem cells (mESCs) versus embroid bodies (EBs). Measuring the mRNA levels by quantitative RT-PCR and the amounts of the respective metabolites by LC-ESI/MS/MS, notable differences between R1 mESCs and EBs were: EBs have higher mRNAs for CerS1 and CerS3, which synthesize C18- and C>or=24-carbons dihydroceramides (DH)Cer, respectively; EBs have higher CerS2 (for C24:0- and C24:1-); and EBs have lower CerS5 + CerS6 (for C16-). In agreement with these findings, EBs have (DH)Cer with higher proportions of C18-, C24- and C26- and less C16-fatty acids, and longer (DH)Cer are also seen in monohexosyl Cers and sphingomyelins. EBs had higher mRNAs for fatty acyl-CoA elongases that produce C18-, C24-, and C26-fatty acyl-CoAs (Elovl3 and Elovl6), and higher amounts of these cosubstrates for CerS. Thus, these studies have found generally good agreement between genomic and metabolomic data in defining that conversion of mESCs to EBs is accompanied by a large number of changes in gene expression and subspecies distributions for both sphingolipids and fatty acyl-CoAs.
School of Biology & Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30332, USA.
Hyejung
H
Park
Christopher A
CA
Haynes
Alison V
AV
Nairn
Michael
M
Kulik
Stephen
S
Dalton
Kelley
K
Moremen
Alfred H
AH
Merrill
D000123:Acetyltransferases / Q000235:genetics; D000214:Acyl Coenzyme A / Q000235:genetics; D000818:Animals; D002518:Ceramides / Q000235:genetics* / Q000378:metabolism*; D053595:Embryonic Stem Cells / Q000378:metabolism*; D044943:Fatty Acid Desaturases / Q000235:genetics; D000081031:Fatty Acid Elongases; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006023:Glycoproteins / Q000096:biosynthesis; D051379:Mice; D020411:Oligonucleotide Array Sequence Analysis; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
D000214:Acyl Coenzyme A; D002518:Ceramides; C000630960:Elovl3 protein, mouse; C000630968:Elovl6 protein, mouse; D006023:Glycoproteins; D012333:RNA, Messenger; C109343:dihydroceramide; D044943:Fatty Acid Desaturases; D000123:Acetyltransferases; D000081031:Fatty Acid Elongases