Abstract
A full-length chicken apolipoprotein A-I (apoAI) cDNA has been cloned into an expression vector, pRSVapoAI. This plasmid was transfected into a monkey kidney (COS-1) cell line in order to study apolipoprotein-lipid assembly. Chicken apoAI is the major apolipoprotein of chicken high-density lipoprotein-lipid assembly. apolipoprotein content than the HDL of human plasma. The transient transfected COS-1 cells synthesized and secreted authentic plasma apoAI. Under serum-free medium conditions, COS cells secreted only proapoAI. A small portion (15%) of the secreted apoAI floated at a density 1.07-1.20 g/ml. Upon incubation with fetal bovine serum at 10°C, a majority of the apoAI was recovered in the HDL density (1.06-1.20 g/ml) region. Secreted apoAI was labeled when transfected COS cells were incubated with [U-14C]palmitate, but the incorporation of radioactivity was not the result of fatty acid acylation through ester bond formation. These results indicate that heterologous COS-1 cells are capable of synthesizing and secreting apoAI, and that intracellular association of apoAI with lipids is not necessary for secretion.
Original language | English (US) |
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Pages (from-to) | 47-53 |
Number of pages | 7 |
Journal | BBA - Gene Structure and Expression |
Volume | 1009 |
Issue number | 1 |
DOIs | |
State | Published - Sep 21 1989 |
Externally published | Yes |
All Science Journal Classification (ASJC) codes
- Structural Biology
- Biophysics
- Biochemistry
- Genetics
Keywords
- (Chicken)
- Apolipoprotein
- HDL
- Lipoprotein assembly
- Secretion
- Transfection