Disease relevance of UL38

• The ORF described here corresponds to the ORF designated UL38 in the recently published nucleotide sequence of the HSV-1 UL region (D. J. McGeoch, M. A. Dalrymple, A. J. Davison, A. Dolan, M. C. Frame, D. McNab, L. J. Perry, J. E. Scott, and P. Taylor, J. Gen. Virol. 69:1531-1574, 1988) [1].
• Assembly of herpes simplex virus (HSV) intermediate capsids in insect cells infected with recombinant baculoviruses expressing HSV capsid proteins [2].
• On the other hand, electron microscopy of mutant-infected cells revealed that neither viral capsids nor capsid-related structures were assembled at the nonpermissive temperature [1].
• Capsid structure of simian cytomegalovirus from cryoelectron microscopy: evidence for tegument attachment sites [3].
• Herpes simplex virus-1 (HSV-1) virions are large, complex enveloped particles containing a proteinaceous tegument layer connected to an icosahedral capsid [4].

High impact information on UL38

• The infectious virion is an enveloped capsid containing the viral polymerase and double-stranded DNA genome [5].
• Antibody titers for viral capsid antigens of all four human herpesviruses were measured by immunofluorescence in the sera of 16 Burkitt's lymphoma (BL) PATIENTS, 16 AGE-, SEX-, AND LOCALITY-MATCHED CONTROLS, AND 136 FAMILY MEMBERS FROM THE West Nile District of Uganda [6].
• Images were obtained of 1) the intact, enveloped virus; 2) the underlying capsid with associated tegument proteins along with fragments of the membrane; 3) the capsomeres composing the capsid and their surface arrangement; 4) damaged and partially degraded capsids with missing capsomeres; and 5) the DNA extruded from damaged virions [7].
• The capsid-associated UL25 protein of the alphaherpesvirus pseudorabies virus is nonessential for cleavage and encapsidation of genomic DNA but is required for nuclear egress of capsids [8].
• Each of these proteins has significant amino acid sequence homology to capsid proteins in alpha- and betaherpesviruses [9].

Chemical compound and disease context of UL38

• The protein kinase associated with purified herpes simplex virus 1 and 2 virions partitioned with the capsid-tegument structures and was not solubilized by non-ionic detergents and low, non-inhibitory concentrations of urea [10].
• To address whether cytomegalovirus (CMV) utilizes the same strategy for capsid assembly, several glutathione S-transferase fusion proteins to the C terminus of the CMV assembly protein precursor were produced and purified from bacterial cells [11].
• An 87 bp DNA fragment from the vp72 capsid protein gene of African Swine Fever virus (ASFV) and the entire Leishmania major glycoprotein gp63 gene were expressed in this system [12].

Biological context of UL38

• We propose a model for infectious entry of HSV-1 by a series of interactions between the virion envelope and the cell plasma membrane that trigger virion disassembly, membrane fusion, and capsid penetration [13].
• Results with recombinant viruses containing modifications of the TATA box or initiator element of the UL38 promoter suggest that DAS functions to increase transcription initiation and not the efficiency of transcription elongation [14].
• The type-common immunoreactivity of the two antisera and comparison of the primary amino acid sequences of the predicted products of the HSV-2 ORF and the equivalent genomic region of HSV-1 provided evidence that the HSV-1 UL38 ORF encodes the HSV-1 ICP32/VP19c [15].
• Transcriptional activation of the herpes simplex virus type 1 UL38 promoter conferred by the cis-acting downstream activation sequence is mediated by a cellular transcription factor [14].
• Previous work on the strict late (gamma) UL38 promoter of herpes simplex virus type 1 identified three cis-acting elements required for wild-type levels of transcription: a TATA box at -31, a consensus mammalian initiator element at the transcription start site, and a downstream activation sequence (DAS) at +20 to +33 [16].

Anatomical context of UL38

• Here we report that ICP35, ICP5, and UL38 (VP19c) coalesce at late times postinfection and form antigenically dense structures located at the periphery of nuclei, close to but not abutting nuclear membranes [17].
• Using this cell line we isolated a null mutant virus in the UL38 ORF and a mutant virus that was altered at residues 610 and 611 of the UL26 and UL26.5 gene products [18].
• Immunolocalization studies on purified virions indicate that the antigen can be detected only in virions without membranes, and is located outside the capsid, most probably in the tegument [19].
• The first principle is that the capsid disassembles in the cytosol or in a docked state at the nuclear pore complex and a subviral genomic complex is trafficked through the pore [20].

Other interactions of UL38

• The cistrons encoding the herpes simplex virus type 1 (HSV-1) UL37 and UL38 genes are adjacent to one another but are transcribed from opposite strands of the viral DNA [21].

Analytical, diagnostic and therapeutic context of UL38

• By immunoelectron microscopy, we detected UL25-specific label on DNA-containing C capsids but not on other intranuclear immature or defective capsid forms [8].
• The mutations that abolished the interaction in the yeast two-hybrid assay also abolished capsid assembly in insect cells [22].
• Although electron microscopy, biochemical, and PCR analyses hinted at a likely reconstitution of capsid maturation, DNA encapsidation could not be confirmed by a traditional SQ test [23].
• Children free from infectious disease have been examined by indirect immunofluorescence for the presence of antibodies to the intracellular capsid antigen of Epstein-Barr virus (EBV) [24].

References