Letter | Published:

Skin shedding and tissue regeneration in African spiny mice (Acomys)

Nature volume 489, pages 561565 (27 September 2012) | Download Citation



Evolutionary modification has produced a spectrum of animal defence traits to escape predation, including the ability to autotomize body parts to elude capture1,2. After autotomy, the missing part is either replaced through regeneration (for example, in urodeles, lizards, arthropods and crustaceans) or permanently lost (such as in mammals). Although most autotomy involves the loss of appendages (legs, chelipeds, antennae or tails, for example), skin autotomy can occur in certain taxa of scincid and gekkonid lizards3. Here we report the first demonstration of skin autotomy in Mammalia (African spiny mice, Acomys). Mechanical testing showed a propensity for skin to tear under very low tension and the absence of a fracture plane. After skin loss, rapid wound contraction was followed by hair follicle regeneration in dorsal skin wounds. Notably, we found that regenerative capacity in Acomys was extended to ear holes, where the mice exhibited complete regeneration of hair follicles, sebaceous glands, dermis and cartilage. Salamanders capable of limb regeneration form a blastema (a mass of lineage-restricted progenitor cells4) after limb loss, and our findings suggest that ear tissue regeneration in Acomys may proceed through the assembly of a similar structure. This study underscores the importance of investigating regenerative phenomena outside of conventional model organisms, and suggests that mammals may retain a higher capacity for regeneration than was previously believed. As re-emergent interest in regenerative medicine seeks to isolate molecular pathways controlling tissue regeneration in mammals, Acomys may prove useful in identifying mechanisms to promote regeneration in lieu of fibrosis and scarring.

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We thank John Kahiro for assisting during materials testing and the Department of Mechanical Engineering, University of Nairobi, for use of their equipment. We thank John Kimani, Stanley Marete and Jackson Mugweru, for help with animal care and materials procurement in Nairobi, Ekiru Ekaran for field assistance, and Bernard Agwanda, Darcy Ogada, and Hillary Young for help with identification and natural history of Acomys. Conversations with Steve Takata and Truman Young drew our attention to this phenomenon.

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  1. Department of Biology, University of Florida, 223 Bartram Hall PO Box 118525 Gainesville, Florida 32610, USA

    • Ashley W. Seifert
    • , Megan G. Seifert
    • , Todd M. Palmer
    •  & Malcolm Maden
  2. Department of Veterinary Anatomy and Physiology, University of Nairobi, PO Box 30197, 00010 Nairobi, Kenya

    • Ashley W. Seifert
    •  & Stephen G. Kiama
  3. Mpala Research Centre, PO Box 555 Nanyuki 10400, Kenya

    • Ashley W. Seifert
    • , Megan G. Seifert
    • , Jacob R. Goheen
    •  & Todd M. Palmer
  4. Department of Zoology and Physiology, and Department of Botany, University of Wyoming, 1000 East University Avenue, Laramie, Wyoming 82071, USA

    • Jacob R. Goheen


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A.W.S., J.R.G., T.M.P. and M.M. formulated the research. A.W.S, M.G.S, M.M. and S.G.K., performed the research and analysed the data. A.W.S. wrote the manuscript and all authors discussed the results, commented on and edited the manuscript.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Ashley W. Seifert.

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