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Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death
Published on: December 27, 2016
A lipocalin sequence signature modulates cell survival.
Ana Marisa Chudzinski-Tavassi1, Linda C Carrijo-Carvalho, Kaline Waismam
1Laboratory of Biochemistry and Biophysics, Butantan Institute, São Paulo, SP, Brazil. amchudzinski@butantan.gov.br
FEBS Letters
|May 18, 2010
Summary
Researchers discovered a conserved seven-amino acid sequence in lipocalins that enhances cell survival. This sequence, found in various lipocalins, shows cytoprotective effects in endothelial cells and leucocytes, dependent on nitric oxide synthase.
Area of Science:
- Biochemistry
- Molecular Biology
- Cell Biology
Background:
- Lipocalins are a diverse superfamily of proteins characterized by a conserved beta-barrel structure.
- These proteins share three conserved sequence motifs, suggesting shared functional properties.
- The role of specific conserved motifs in lipocalin function, particularly in cell survival, remains incompletely understood.
Purpose of the Study:
- To identify and characterize conserved functional sequences within the lipocalin family.
- To investigate the role of a specific conserved motif (motif 2) in modulating cell survival.
- To explore the potential cytoprotective activity of lipocalin-derived peptides.
Main Methods:
- Peptide mapping was employed to identify conserved amino acid sequences within lipocalins.
- A synthetic peptide based on an insect lipocalin sequence motif was synthesized.
- Cytoprotective activity was assessed in serum-deprived endothelial cells and leucocytes.
- The involvement of nitric oxide synthase in the observed cytoprotective effects was investigated.
Main Results:
- A seven-amino acid sequence, related to lipocalin motif 2, was identified as modulating cell survival.
- The synthetic lipocalin-derived peptide demonstrated significant cytoprotective activity in endothelial cells and leucocytes under serum deprivation.
- This cytoprotective effect was found to be dependent on nitric oxide synthase activity.
- The identified sequence was present in various known lipocalins, including apolipoprotein D and retinol binding protein, as well as numerous uncharacterized proteins.
Conclusions:
- The seven-amino acid sequence represents a conserved functional signature within the lipocalin superfamily.
- This sequence confers cytoprotective properties, mediated by nitric oxide synthase.
- The findings suggest a conserved role for this sequence in promoting cell survival across different lipocalins.
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