Biology Reference
In-Depth Information
Functions of Human Cytomegalovirus
Tegument Proteins Prior to Immediate Early
Gene Expression
R. F. Kalejta
Contents
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
Tegument Proteins Known to Act at the Very Start of HCMV Infection . . . . . . . . . . . . . . . . 104
Delivery of the Genome to the Nucleus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
Initiating Viral IE Gene Expression. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
Model for Postfusion, Preimmediate Early Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Perspectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
Abstract
Proteins within the tegument layer of herpesviruses such as human cytome-
galovirus (HCMV) are released into the cell upon entry when the viral envelope fuses
with the cell membrane. These proteins are fully formed and active, and they mediate
key events at the very start of the lytic infectious cycle, including the delivery of the
viral genome to the nucleus and the initiation of viral gene expression. This review
examines what is known about tegument protein function prior to the immediate early
(IE) phase of the viral lytic replication cycle and identifies key questions that need to
be answered to better understand how these proteins promote HCMV infection so that
antiviral treatments that target these important viral regulators can be developed.
Introduction
Human cytomegalovirus (HCMV) is a significant human pathogen that infects the
majority of the world's population. Viral infection causes birth defects and severe
disease in patients with suppressed immune function and is associated with
age-related immunosenescence, cancer, and cardiovascular disease (Mocarski
R.F. Kalejta
Institute for Molecular Virology and McArdle Laboratory for Cancer Research, University
of Wisconsin-Madison , Madison , WI 53706-1596 , USA
rfkalejta@wisc.edu
