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Identification of Plasmodesmal Localization Sequences in Proteins In Planta
08:07

Identification of Plasmodesmal Localization Sequences in Proteins In Planta

Published on: August 15, 2017

Plasmatocyte spreading peptide is encoded by an mRNA differentially expressed in tissues of the moth Pseudoplusia

K D Clark1, A Witherell, M R Strand

  • 1Department of Entomology, University of Wisconsin-Madison 53706, USA.

Biochemical and Biophysical Research Communications
|October 1, 1998
PubMed

Insights

Researchers identified a gene (p15) encoding a precursor to plasmatocyte spreading peptide (PSP1), a key regulator of insect immune cell function. This finding sheds light on the molecular mechanisms of the invertebrate immune system.

Area of Science:

  • Insect immunology
  • Molecular biology
  • Biochemistry

Background:

  • Hemocytes are crucial for invertebrate immunity, but the molecules regulating their function are largely unknown.
  • Plasmatocyte spreading peptide (PSP1) was previously identified as a regulator of plasmatocyte trafficking and adhesion in moths.
  • The molecular basis of PSP1 function and its production pathway remain to be elucidated.

Purpose of the Study:

  • To clone the cDNA encoding a PSP1 precursor protein.
  • To investigate the expression patterns of PSP1-related genes in the moth Pseudoplusia includens.
  • To confirm the production of PSP1 precursor proteins.

Main Methods:

  • cDNA cloning and sequencing
  • Northern blot analysis for gene expression profiling
  • In vitro transcription/translation assays
  • Immunoblotting using PSP1 polyclonal antibodies

Main Results:

  • A cDNA (p15) encoding a PSP1 precursor protein was successfully cloned.
  • Homologous prepro-PSP1 mRNA is expressed in the fat body, with related transcripts found in nervous tissue and hemocytes.
  • In vitro transcription/translation of p15 produced a protein recognized by PSP1 antibodies, and a pro-PSP1 protein was detected in plasma and fat body.

Conclusions:

  • The gene p15 encodes a precursor for PSP1, providing insight into its synthesis.
  • PSP1 and related molecules are expressed in multiple tissues, suggesting diverse roles in the immune system and potentially beyond.
  • The presence of pro-PSP1 in plasma and fat body indicates its processing and potential secretion.

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