Chen et al. report that retaining the cytoplasmic domain of Env proteins may be important to attract bNAbs. (science.sciencemag.org)
The illustrations (orange) of the two categories of Env protein are based on negative - stain EM. (science.sciencemag.org)
We identified a single amino acid substitution (Y302N) present in Env isolated from X4 - ZFN mice but not R5 - ZFN mice or the viral innoculum. (journals.plos.org)