Somitovasculin, a novel endothelial-specific transcript involved in the vasculature development.
OBJECTIVE
We recently isolated and characterized endothelial-like CD31(+) cells derived from mouse embryonic stem (mES) cells and identified their transcriptome. The main objective of this study was to determine the functional relevance of the transcripts of unknown function (TUF) for vasculature development.


RESULTS
We selected 2 TUFs of more than 27 to study their role for blood vessel development in zebrafish. Morpholino (MO) knockdown of the zebrafish orthologs of the first TUF (TUF1, mouse cDNA BC022623) showed disruption of the intersegmental vessels (ISV) at 2 days postfertilization as observed by live imaging of fli:EGFP-transgenic embryos. The morphants showed abnormal blood circulation, but no effect on hematopoiesis was observed as demonstrated by gata-1 in situ hybridizations. Because knockdown of TUF1 resulted in disruption of the ISV patterning we named the TUF1 somitovasculin. TUF2 has been identified as cDNA clone BC020535. The MO knockdown of TUF2 resulted in a phenotype with an enlarged heart and the embryos lacked circulation completely.


CONCLUSIONS
We have shown the participation of a novel transcript (named somitovasculin) in circulatory vessel development. The combination of expression profiling in differentiating mES cells and the zebrafish model has the potential for rapid identification and functional characterization of TUFs.
Mariappan
Devi
D
University of Cologne, Center of Physiology and Pathophysiology, Institute of Neurophysiology, Cologne, Germany.
Niemann
Rabea
R
Gajewski
Martin
M
Winkler
Johannes
J
Chen
Shuhua
S
Choorapoikayil
Suma
S
Bitzer
Marco
M
Schulz
Herbert
H
Hescheler
Jürgen
J
Sachinidis
Agapios
A
D000818:Animals; D001483:Base Sequence; D001808:Blood Vessels / Q000196:embryology* / Q000378:metabolism; D019521:Body Patterning / Q000235:genetics*; D002454:Cell Differentiation; D002478:Cells, Cultured; D053595:Embryonic Stem Cells / Q000166:cytology / Q000378:metabolism; D004730:Endothelium, Vascular / Q000166:cytology / Q000196:embryology / Q000378:metabolism; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D017403:In Situ Hybridization; D051379:Mice; D038081:Organogenesis / Q000235:genetics* / Q000502:physiology; D011336:Probability; D012333:RNA, Messenger / Q000032:analysis; D012016:Reference Values; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology*; D015027:Zebrafish / Q000196:embryology* / Q000378:metabolism; D029961:Zebrafish Proteins / Q000235:genetics / Q000378:metabolism*
D012333:RNA, Messenger; D014157:Transcription Factors; D029961:Zebrafish Proteins