Transcriptional deregulation and a missense mutation define ANKRD1 as a candidate gene for total anomalous pulmonary venous return.
Total anomalous pulmonary venous return (TAPVR) is a congenital heart defect in which the pulmonary veins fail to enter the left atrium and drain instead into the right atrium or one of its venous tributaries. Although a genetic basis for TAPVR has long been recognized, no single gene involved in the pathogenesis of this disease has been identified to date. We previously reported a TAPVR patient bearing a de novo 10;21 balanced translocation. In this work, we cloned both translocation breakpoints from this patient and mapped the ANKRD1 gene, encoding a cardiac transcriptional regulator, 130 kb proximally to the breakpoint on chromosome 10. In situ hybridization analysis performed on murine embryos showed ANKRD1 expression in the developing pulmonary veins, suggesting a possible role for this gene in TAPVR pathogenesis. Moreover, ANKRD1 expression levels were found to be highly increased in lymphoblastoid cell lines derived from both the translocation-bearing proband and a second independent sporadic TAPVR patient, suggesting that disruption of the normal ANKRD1 expression pattern is associated with TAPVR. Finally, a nonconservative missense mutation in the ANKRD1 gene was found in a third sporadic TAPVR patient. In vitro calpain-mediated degradation assays, coupled to reporter gene analysis in transfected HeLa cells, strongly suggested that this mutation enhances both the stability of the ANKRD1/CARP protein and its transcriptional repression activity upon the cardiac-specific atrial natriuretic factor (ANF) promoter. Taken together, these results define ANKRD1 as a possible candidate gene for TAPVR pathogenesis.
Cinquetti
Raffaella
R
Department of Biotechnology and Molecular Sciences, University of Insubria, Varese, Italy.
Badi
Ileana
I
Campione
Marina
M
Bortoletto
Elisabetta
E
Chiesa
Giulia
G
Parolini
Cinzia
C
Camesasca
Chiara
C
Russo
Antonella
A
Taramelli
Roberto
R
Acquati
Francesco
F
D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D002879:Chromosomes, Human, Pair 10 / Q000235:genetics; D002891:Chromosomes, Human, Pair 21 / Q000235:genetics; D004247:DNA / Q000235:genetics; D005260:Female; D015870:Gene Expression; D006367:HeLa Cells; D006330:Heart Defects, Congenital / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D008297:Male; D051379:Mice; D009124:Muscle Proteins / Q000235:genetics* / Q000378:metabolism; D020125:Mutation, Missense; D009687:Nuclear Proteins / Q000235:genetics* / Q000378:metabolism; D010375:Pedigree; D011247:Pregnancy; D011667:Pulmonary Veins / Q000002:abnormalities*; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics* / Q000378:metabolism; D014158:Transcription, Genetic; D014162:Transfection; D014178:Translocation, Genetic
C491304:ANKRD1 protein, human; D009124:Muscle Proteins; D009687:Nuclear Proteins; D011994:Recombinant Proteins; D012097:Repressor Proteins; D004247:DNA