Both PIGA and PIGL mutations cause GPI‐a deficient isolates in the Tk6 cell line. (13th May 2015)

• Record Type: Journal Article
• Authors: Nicklas, Janice A.; Carter, Elizabeth W.; Albertini, Richard J.
• Is Part Of: Environmental and molecular mutagenesis. Volume 56:Number 8(2015:Oct.)
• Page Start: 663
• Page End: 673
• Publication Date: 2015-05-13
• Subjects: Mutagenesis -- Periodicals; Molecular genetics -- Periodicals; Mutagenèse -- Périodiques; Mutagenèse chimique -- Périodiques; Mutation -- Périodiques; Maladies de l'environnement -- Périodiques; Génétique moléculaire -- Périodiques; 576.542
• DOI: 10.1002/em.21953
• Languages: English
• ISSNs: 0893-6692

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <p>Molecular analysis of proaerolysin selected glycosylphosphatidylinositol anchor (GPI‐a) deficient isolates in the TK6 cell line was performed. Initial studies found that the expected X‐linked <italic>PIGA</italic> mutations were rare among the spontaneous isolates but did increase modestly after ethyl methane sulfate (EMS) treatment (but to only 50% of isolates). To determine the molecular bases of the remaining GPI‐a deficient isolates, real‐time analysis for all the 25 autosomal GPI‐a pathway genes was performed on the isolates without <italic>PIGA</italic> mutations, determining that <italic>PIGL</italic> mRNA was absent for many. Further analysis determined these isolates had several different homozygous deletions of the 5′ region of <italic>PIGL</italic> (17p12‐p22) extending 5′ (telomeric) through <italic>NCOR1</italic> and some into the <italic>TTC19</italic> gene (total deletion >250, 000 bp). It was determined that the TK6 parent had a hemizygous deletion in 17p12‐p22 (275, 712 bp) extending from <italic>PIGL</italic> intron 2 into <italic>TTC19</italic> intron 7. Second hit deletions in the other allele in the GPI‐a deficient isolates led to the detected homozygous deletions. Several of the deletion breakpoints including the original first hit deletion were sequenced. As strong support for TK6 having a deletion, a number of the isolates without <italic>PIGA</italic> mutations nor homozygous <italic>PIGL</italic> deletions had point mutations in the <italic>PIGL</italic> gene. These studies show that the GPI‐a mutation studies using TK6 cell line could be a valuable assay detecting point and deletion mutations in two genes simultaneously. Environ. Mol. Mutagen. 56:663–673, 2015. © 2015 Wiley Periodicals, Inc.</p> </abstract>