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The clathrin assembly protein PICALM is required for erythroid maturation and transferrin internalization in mice

Mai Suzuki1, Hirokazu Tanaka, Akira Tanimura

  • 1Department of Biological Science, Graduate School of Humanities and Sciences, Nara Women's University, Nara, Japan.

Plos One
|February 25, 2012
PubMed

Insights

Phosphatidylinositol binding clathrin assembly protein (CALM) is essential for mouse growth and survival. CALM deficiency causes severe anemia and impaired transferrin uptake, highlighting its critical role in erythroid maturation.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Hematology

Background:

  • Phosphatidylinositol binding clathrin assembly protein (PICALM), also known as clathrin assembly lymphoid myeloid leukemia protein (CALM), is involved in clathrin assembly and vesicle formation.
  • Its precise physiological function in vivo remained largely unknown.

Purpose of the Study:

  • To investigate the in vivo physiological role of CALM using a mouse model.

Main Methods:

  • Generation and analysis of CALM-deficient mice.
  • Assessment of growth, lifespan, erythroid maturation, and iron content.
  • Evaluation of clathrin-mediated endocytosis in erythroid cells and fibroblasts.

Main Results:

  • CALM-deficient mice displayed growth retardation, dwarfism, and shortened lifespans.
  • Severe anemia was observed, with impaired erythroid precursor maturation and iron content.
  • Impaired transferrin internalization via clathrin-mediated endocytosis was evident in CALM-deficient cells.

Conclusions:

  • CALM is crucial for normal erythroid maturation in mice.
  • CALM plays a vital role in transferrin internalization, essential for erythroid development.

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