title: Genetic basis of hindlimb loss in a naturally occurring vertebrate model.
abstract: Here we genetically characterise pelvic finless, a naturally occurring model of hindlimb loss in zebrafish that lacks pelvic fin structures, which are homologous to tetrapod hindlimbs, but displays no other abnormalities. Using a hybrid positional cloning and next generation sequencing approach, we identified mutations in the nuclear localisation signal (NLS) of T-box transcription factor 4 (Tbx4) that impair nuclear localisation of the protein, resulting in altered gene expression patterns during pelvic fin development and the failure of pelvic fin development. Using a TALEN-induced tbx4 knockout allele we confirm that mutations within the Tbx4 NLS (A78V; G79A) are sufficient to disrupt pelvic fin development. By combining histological, genetic, and cellular approaches we show that the hindlimb initiation gene tbx4 has an evolutionarily conserved, essential role in pelvic fin development. In addition, our novel viable model of hindlimb deficiency is likely to facilitate the elucidation of the detailed molecular mechanisms through which Tbx4 functions during pelvic fin and hindlimb development.
authors.affiliation: Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, New South Wales 2109, Australia Department of Anatomy & Histology, School of Medical Sciences and Bosch Institute, University of Sydney, Sydney, New South Wales 2006, Australia.
authors.forename: Emily K
authors.initials: EK
authors.lastname: Don
authors.affiliation: Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia.
authors.forename: Tanya A
authors.initials: TA
authors.lastname: de Jong-Curtain
authors.affiliation: Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia.
authors.forename: Karen
authors.initials: K
authors.lastname: Doggett
authors.affiliation: Institute for Molecular Bioscience, University of Queensland, St Lucia, Brisbane, Queensland 4072, Australia.
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Hall
authors.affiliation: Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, New South Wales 2109, Australia.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Heng
authors.affiliation: Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, New South Wales 2109, Australia.
authors.forename: Andrew P
authors.initials: AP
authors.lastname: Badrock
authors.affiliation: Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, New South Wales 2109, Australia.
authors.forename: Claire
authors.initials: C
authors.lastname: Winnick
authors.affiliation: Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, New South Wales 2109, Australia.
authors.forename: Garth A
authors.initials: GA
authors.lastname: Nicholson
authors.affiliation: Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, New South Wales 2109, Australia.
authors.forename: Gilles J
authors.initials: GJ
authors.lastname: Guillemin
authors.affiliation: Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria 3800, Australia.
authors.forename: Peter D
authors.initials: PD
authors.lastname: Currie
authors.affiliation: Garvan Institute of Medical Research, Diabetes and Metabolism Division, Sydney, New South Wales 2010, Australia St. Vincent's Clinical School, UNSW Australia, Sydney, New South Wales 2052, Australia.
authors.forename: Daniel
authors.initials: D
authors.lastname: Hesselson
authors.affiliation: Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia.
authors.forename: Joan K
authors.initials: JK
authors.lastname: Heath
authors.affiliation: Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, New South Wales 2109, Australia Department of Anatomy & Histology, School of Medical Sciences and Bosch Institute, University of Sydney, Sydney, New South Wales 2006, Australia nicholas.cole@mq.edu.au.
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Cole
keywords: Development; Hindlimb; Pelvic fin; TALENs; Tbx4