Differential functional effects of novel mutations of the transcription factor FOXL2 in BPES patients.
Mutations of the transcription factor FOXL2, involved in cranio-facial and ovarian development lead to the Blepharophimosis-Ptosis-Epicanthus Inversus Syndrome (BPES) in human. Here, we describe nine mutations in the open reading frame of FOXL2. Six of them are novel: c.292T>A (p.Trp98Arg), c.323T>C (p.Leu108Pro), c.650C>G (p.Ser217Cys) and three frameshifts. We have performed localization and functional studies for three of them. We have observed a strong cytoplasmic mislocalization induced by the missense mutation p.Leu108Pro located in the forkhead (FKH) domain of FOXL2. In line with this, transcriptional activity assays confirmed the loss-of-function induced by this variant. Interestingly, the novel mutation p.Ser217Cys, mapping between the FKH and the polyalanine domain of FOXL2 and producing a mild eyelid phenotype, led to normal localization and transactivation. We have also modeled the structure of the FKH domain to explore the potential structural impact of the mutations reported here and other previously reported ones. This analysis shows that mutants can be sorted into two classes: those that potentially alter protein-protein interactions and those that might disrupt the interactions with DNA. Our findings reveal new insights into the molecular effects of FOXL2 mutations, especially those affecting the FKH binding domain. (c) 2008 Wiley-Liss, Inc.
Nallathambi
Jeyabalan
J
Department of Genetics, Dr. G.Venkataswamy Eye Research Institute, Aravind Medical Research Foundation, Aravind Eye Hospital, Madurai 625020, India.
Laissue
Paul
P
Batista
Frank
F
Benayoun
Bérénice A
BA
Lesaffre
Corinne
C
Moumné
Lara
L
Pandaranayaka
Pj Eswari
PE
Usha
Kim
K
Krishnaswamy
Sankaran
S
Sundaresan
Periasamy
P
Veitia
Reiner A
RA
D000818:Animals; D016569:Blepharophimosis / Q000235:genetics*; D019556:COS Cells; D002648:Child; D002675:Child, Preschool; D002522:Chlorocebus aethiops; D005260:Female; D000074842:Forkhead Box Protein L2; D051858:Forkhead Transcription Factors / Q000235:genetics* / Q000502:physiology*; D016368:Frameshift Mutation; D006801:Humans; D007223:Infant; D008297:Male; D009154:Mutation; D016649:Primary Ovarian Insufficiency / Q000235:genetics; D017434:Protein Structure, Tertiary
C421604:FOXL2 protein, human; D000074842:Forkhead Box Protein L2; D051858:Forkhead Transcription Factors