Molecular characterization and immunohistochemical localization of palmdelphin, a cytosolic isoform of the paralemmin protein family implicated in membrane dynamics

Eur J Cell Biol. 2005 Nov;84(11):853-66. doi: 10.1016/j.ejcb.2005.07.002.


Palmdelphin is a newly identified cytosolic isoform of paralemmin-1, a lipid raft-associated protein implicated in cell shape control. Like paralemmin-1, palmdelphin is phosphorylated, giving rise to electrophoretic band heterogeneity that is most pronounced in the brain. In ultracentrifugation and gel filtration palmdelphin behaves as a non-globular monomer. Its C-terminal region binds glutamine synthetase. Immunohistochemical analysis of the rat brain shows a prominent localization of palmdelphin in the cerebral cortex, hippocampus, amygdala, septum, indusium griseum, piriform cortex, nucleus supraopticus, and nucleus of the lateral olfactory tract. Many of the circumscript palmdelphin-positive areas are related to the olfactory system. Immunoperoxidase electron microscopy reveals a discontinuous distribution of palmdelphin immunoreactivity, in the form of spots scattered throughout the cytoplasm of selected neuronal perikarya and dendrites, including dendritic spines, often in association with endomembranes, and in a pattern which is similar to that of the cytoplasmic fraction of paralemmin-1. In subcellular fractionation experiments palmdelphin behaves as a cytosolic protein which, however, can be partially recruited from cytosol to the detergent-resistant fraction of a membrane/cytoskeletal cell ghost preparation. These observations suggest that palmdelphin may peripherally associate with endomembranes or cytoskeleton-linked structures.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • COS Cells
  • Cell Membrane / metabolism*
  • Chlorocebus aethiops
  • Cytosol / chemistry*
  • Fluorescein-5-isothiocyanate
  • Fluorescent Antibody Technique, Indirect
  • Fluorescent Dyes
  • Glutamate-Ammonia Ligase / metabolism
  • Glutathione Transferase / metabolism
  • Immunohistochemistry*
  • Membrane Proteins / analysis
  • Membrane Proteins / chemistry*
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Membrane Proteins / ultrastructure
  • Mice
  • Microscopy, Fluorescence
  • Molecular Sequence Data
  • Peroxidase / metabolism
  • Peroxidase / ultrastructure
  • Phosphorylation
  • Protein Isoforms / chemistry
  • Protein Isoforms / genetics
  • Protein Isoforms / metabolism
  • Protein Isoforms / ultrastructure
  • Rats
  • Rats, Wistar
  • Recombinant Fusion Proteins / metabolism
  • Sequence Homology, Amino Acid
  • Tissue Distribution


  • Fluorescent Dyes
  • Membrane Proteins
  • Palmd protein, mouse
  • Protein Isoforms
  • Recombinant Fusion Proteins
  • Peroxidase
  • Glutathione Transferase
  • Glutamate-Ammonia Ligase
  • Fluorescein-5-isothiocyanate