The influence of myristoylation, liposome surface charge and nucleic acid interaction in the partition properties of HIV-1 Gag-N-terminal peptides to membranes

PÉREZ SOCAS, LUIS BENITO; AMBROGGIO, ERNESTO ESTEBAN

BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES

ELSEVIER SCIENCE BV

Año: 2020 vol. 1862

0005-2736

he group-specific antigen (GAG) polyprotein of HIV-1 is the main coordinator of the virus assembly process at the plasma membrane (PM) and is directed by its N-terminal matrix domain (MA). MA is myristoylated and possess a highly basic region (HBR) responsible for the interaction with the negative lipids of the PM, especially with PIP2. In addition, MA binds RNA molecules proposed as a regulatory step of the assembly process. Here we study the interaction of a synthetic peptide (N-terminal 21 amino acids of MA) and liposomes of different compositions using a variety of biophysical techniques. Particularly, we use the fluorescence properties of the single tryptophan of the peptide to analyze its partition to membranes, where we harness for first time the analytical ability of spectral phasors method to study this interaction. We found that electrostatic interactions play an important role for peptide partition to membranes and myristoylation reduces the free energy of the process. Inte