Intramolecular complementation of measles virus fusion protein stability confers cell-cell fusion activity at 37 degree C

• Published in: FEBS letters Vol. 589; no. 1; pp. 152 - 158
• Main Authors: Satoh, Yuto, Hirose, Mitsuhiro, Shogaki, Hiroko, Wakimoto, Hiroshi, Kitagawa, Yoshinori, Gotoh, Bin, Takahashi, Ken-ichi, Itoh, Masae
• Format: Journal Article
• Language: English
• Published: 01.01.2015
• Subjects: Measles virus
• ISSN: 0014-5793
• DOI: 10.1016/j.febslet.2014.11.040

The fusion (F) protein of measles virus mediates membrane fusion. In this study, we investigated the molecular basis of the cell-cell fusion activity of the F protein. The N465H substitution in the heptad repeat B domain of the stalk region of the F protein eliminates this activity, but an additional mutation in the DIII domain of the head region - N183D, F217L, P219S, I225T or G240R - restores cell-cell fusion. Thermodynamically stabilized by the N465H substitution, the F protein required elevated temperature as high as 40 degree C to promote cell-cell fusion, whereas all five DIII mutations caused destabilization of the F protein allowing the highest fusion activity at 30 degree C. Stability complementation between the two domains conferred an efficient cell-cell fusion activity on the F protein at 37 degree C.