August 2012, 3:16,
Open Access This content is freely available online to anyone, anywhere at any time.
Date: 09 Aug 2012
Transcriptional heterochrony in talpid mole autopods
Talpid moles show many specializations in their adult skeleton linked to fossoriality, including enlarged hands when compared to the feet. Heterochrony in developmental mechanisms is hypothesized to account for morphological evolution in skeletal elements.
The temporal and spatial distribution of SOX9 expression, which is an early marker of chondrification, is analyzed in autopods of the fossorial Iberian mole Talpa occidentalis, as well as in shrew (Cryptotis parva) and mouse (Mus musculus) for comparison.
Results and discussion
SOX9 expression is advanced in the forelimb compared to the hind limb in the talpid mole. In contrast, in the shrew and the mouse, which do not show fossorial specializations in their autopods, it is synchronous. We provide evidence that transcriptional heterochrony affects the development of talpid autopods, an example of developmental penetrance. We discuss our data in the light of earlier reported pattern heterochrony and later morphological variation in talpid limbs.
Transcriptional heterochrony in SOX9 expression is found in talpid autopods, which is likely to account for pattern heterochrony in chondral limb development as well as size variation in adult fore- and hind limbs.
Slonaker JR: Some morphological changes for adaptation in the mole. J Morphol 1920, 34:335–365.CrossRef
Mitgutsch C, Richardson MK, Jiménez R, Martin JE, Kondrashov P, de Bakker MAG, Sánchez-Villagra MR: Circumventing the polydactyly ‘constraint’: the mole’s thumb. Biol Letters 2012, 8:74–77.CrossRef
Meredith RW, Janecka JE, Gatesy J, Ryder OA, Fisher CA, Teeling EC, Goodbla A, Eizirik E, Simão TLL, Stadler T, Rabosky DL, Honeycutt RL, Flynn JJ, Ingram CM, Steiner C, Williams TL, Robinson TJ, Burk-Herrick A, Westerman M, Ayoub NA, Springer MA, Murphy WJ: Impacts of the Cretaceous terrestrial revolution and KPg extinction on mammal diversification. Science 2011, 334:521–524.PubMedCrossRef
Mitgutsch C, Richardson MK, de Bakker MAG, Jiménez R, Martín JE, Kondrashov P, Sánchez-Villagra MR: From Clone to Bone: the Synergy of Morphological and Molecular Tools in Palaeobiology. In A molecular-morphological study of a peculiar limb morphology: the development and evolution of the mole’s ‘thumb’. Edited by: Asher RJ, Müller J. Cambridge University Press, ; . In press
Adams DC, Nistri A: Ontogenetic convergence and evolution of foot morphology in European cave salamanders (Family: Plethodontidae). BMC Evol Biol 2010, 10:1–10.CrossRef
Richardson MK, Gobes SMH, van Leuwen AC, Polman JAE, Pieau C, Sánchez-Villagra MR: Heterochrony in limb evolution: developmental mechanisms and natural selection. J ExpZool 2009, 312B:639–664.
Mackem S, Mahon KA: Ghox-7: a chick homeobox gene expressed primarily in the limb buds with limb-type differences in expression. Development 1991, 113:791–806.
Mitgutsch C, Olsson L, Haas A: Early embryogenesis in discoglossoid frogs: a study of heterochrony at different taxonomic levels. J Zool Syst Evol Res 2009, 47:248–257.CrossRef
Weisbecker V, Mitgutsch C: A large-scale survey of heterochrony in anuran cranial ossification patterns. J Zool Syst Evol Res 2010, 48:332–347.CrossRef
Werneburg I, Sánchez-Villagra MR: The early development of the Echidna, Tachyglossus aculeatus(Mammalia: Monotremata) and the Grundmuster of mammalian development. Acta Zool-Stockholm 2011, 92:75–88.CrossRef
- Transcriptional heterochrony in talpid mole autopods
- Open Access
- Available under Open Access This content is freely available online to anyone, anywhere at any time.
- Online Date
- August 2012
- Online ISSN
- BioMed Central
- Additional Links
- SOX9 expression
- Developmental penetrance
- Author Affiliations
- 1. Paläontologisches Institut und Museum, Universität Zürich, Karl-Schmid-Strasse 4, Zürich, 8006, Switzerland
- 2. RIKEN Center for Developmental Biology, Laboratory for Evolutionary Morphology, 2-2-3 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo, 650-0047, Japan
- 3. Institute of Biology, University of Leiden, Sylviusweg 72, Leiden, BE 2333, The Netherlands
- 4. Departamento de Genética, Universidad de Granada, Avenida del Conocimiento, Granada, Armilla, 18100, Spain