TCDB is operated by the Saier Lab Bioinformatics Group

1.A.99 The Infectious Bronchitis Virus Envelope Small Membrane Protein E (IBV-E) Family. 

The E protein is a 108 aa, 2 TMS protein belived to be a viroporin.  It interacts with the membrane (M) protein (Lim et al. 2001). The E protein is a component of the viral envelope that plays a central role in virus morphogenesis and assembly. It seems to be important for creating the membrane curvature needed to acquire the rounded, stable and infectious particle phenotype. The E protein acts as a viroporin, inducing the formation of hydrophilic pores in cellular membranes, and it induces apoptosis.

References associated with 1.A.99 family:

Lim, K.P., H.Y. Xu, and D.X. Liu. (2001). Physical interaction between the membrane (M) and envelope (E) proteins of the coronavirus avian infectious bronchitis virus (IBV). Adv Exp Med Biol 494: 595-602. 11774531
Pendleton, A.R. and C.E. Machamer. (2008). Generating antibodies to the gene 3 proteins of infectious bronchitis virus. Methods Mol Biol 454: 163-189. 19057877