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VIP17/MAL, a proteolipid in apical transport vesicles
D Zacchetti1, J Peränen, M Murata
1Cell Biology Programme, European Molecular Biology Laboratory, Heidelberg, Germany.
FEBS Letters
|December 27, 1995
Summary
VIP17, a proteolipid also known as MAL protein, is crucial for directing proteins to the apical surface in cells. This study reveals its role in the vesicular transport machinery from the Golgi to the plasma membrane.
Area of Science:
- Cell biology
- Molecular biology
- Protein trafficking
Background:
- VIP17 (Vesicular Integral Protein of 17 kDa) is a proteolipid found in specific cell compartments.
- It is implicated as a potential component in the machinery for apical protein sorting and targeting.
Purpose of the Study:
- To identify and characterize VIP17.
- To investigate the role of VIP17/MAL in protein trafficking to the apical surface.
Main Methods:
- Cloning and sequencing of the VIP17 cDNA.
- Expression of epitope-tagged VIP17/MAL in Madin-Darby canine kidney (MDCK) and baby hamster kidney (BHK) cells.
- Immunofluorescence microscopy to determine protein localization.
Main Results:
- VIP17 was identified as the canine homolog of human and rat MAL proteins.
- Immunofluorescence revealed VIP17/MAL localized to perinuclear, vesicular, and plasma membrane structures.
- In MDCK cells, VIP17/MAL was predominantly found in apical cytoplasmic vesicles.
Conclusions:
- VIP17/MAL is a key component involved in the trafficking of proteins to the apical plasma membrane.
- The protein plays a significant role in the vesicular transport pathway between the Golgi complex and the apical cell surface.
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