Mrp3, a mitogen-regulated protein/proliferin gene expressed in wound healing and in hair follicles

J T Fassett1, M Nilsen-Hamilton

  • 1Molecular, Cellular and Developmental Biology Program, Iowa State University, Ames, Iowa 50011, USA.

Endocrinology
|April 24, 2001
PubMed

Insights

Mitogen-regulated protein 3 (MRP3) is a growth factor found in skin wound healing and hair follicle cycling. Its gene regulatory sequences are activated during these processes, suggesting a role in tissue repair and hair growth.

Area of Science:

  • Molecular Biology
  • Dermatology
  • Developmental Biology

Background:

  • Growth factors are crucial for cell migration and proliferation during tissue repair.
  • Mitogen-regulated protein (MRP)/proliferin proteins function as growth and angiogenesis factors.

Purpose of the Study:

  • To investigate the role of Mrp3 in cutaneous wound healing and hair follicle cycling.
  • To identify regulatory elements controlling Mrp3 expression during these physiological processes.

Main Methods:

  • Analysis of Mrp3 expression in wound edge keratinocytes and hair follicles.
  • In vitro studies using cultured keratinocytes stimulated with various growth factors.
  • Generation and analysis of transgenic mice with Mrp3 regulatory sequences driving lacZ expression.

Main Results:

  • Mrp3 expression is induced in wound edge keratinocytes during cutaneous wound healing.
  • Mrp3 is temporally expressed in the outer root sheath of hair follicles during the late anagen phase.
  • Keratinocyte growth factor induces Mrp3 in cultured keratinocytes.
  • Transgenic mice show wound- and hair cycle-induced transgene expression, indicating regulatory elements within Mrp3 flanking sequences.

Conclusions:

  • Mrp3 gene expression is regulated by elements within its flanking sequences in response to wound healing and hair cycle events.
  • MRP3 likely participates in wound healing and hair follicle cycling as a growth factor and/or angiogenesis factor.

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