Studies of the broader autism phenotype, and of subtle changes in autism symptoms over time, have been compromised by a lack of established quantitative assessment tools. The Social Responsiveness Scale (SRS-formerly known as the Social Reciprocity Scale) is a new instrument that can be completed by parents and/or teachers in 15-20 minutes. We compared the SRS with the Autism Diagnostic Interview-Revised (ADI-R) in 61 child psychiatric patients. Correlations between SRS scores and ADI-R algorithm scores for DSM-IV criterion sets were on the order of 0.7. SRS scores were unrelated to I.Q. and exhibited inter-rater reliability on the order of 0.8. The SRS is a valid quantitative measure of autistic traits, feasible for use in clinical settings and for large-scale research studies of autism spectrum conditions.

The hepadnaviral polymerase (P) functions in a complex with viral nucleic acids and cellular chaperones. To begin to identify contacts between P and its partners, we assessed the exposure of the epitopes of six monoclonal antibodies (MAbs) to the terminal protein domain of the duck hepatitis B virus P protein in a partially denaturing buffer (RIPA) and a physiological buffer (IPP150). All MAbs immunoprecipitated in vitro translated P well in RIPA, but three immunoprecipitated P poorly in IPP150. Therefore, the epitopes for these MAbs were obscured in the native conformation of P but were exposed when P was in RIPA. Epitopes for MAbs that immunoprecipitated P poorly in IPP150 were between amino acids (aa) 138 and 202. Mutation of a highly conserved motif within this region (T3; aa 176 to 183) improved the immunoprecipitation of P by these MAbs and simultaneously inhibited DNA priming by P. Peptides containing the T3 motif inhibited DNA priming in a dose-dependent manner, whereas eight irrelevant peptides did not. T3 function appears to be conserved among the hepadnaviruses because mutating T3 ablated DNA synthesis in both duck hepatitis B virus and hepatitis B virus. These results indicate that (i) the conserved T3 motif is a molecular contact point whose ligand can be competed by soluble T3 peptides, (ii) the occupancy of T3 obscures the epitopes for three MAbs, and (iii) proper occupancy of T3 by its ligand is essential for DNA priming. Therefore, small-molecule ligands that compete for binding to T3 with its natural ligand could form a novel class of antiviral drugs.Hepatitis B virus (HBV) is a small DNA virus that replicates by reverse transcription (reviewed in reference 9). It has a lipid envelope studded with viral glycoproteins that surrounds an icosahedral core particle composed of the core protein. Within the core particle are the viral nucleic acids and reverse transcriptase (P). Other hepadnaviruses infect woolly monkeys, woodchucks, ground squirrels, ducks, geese, and herons (6,17,29,31,32). Significant differences exist among the hepadnaviruses, but they share a high degree of hepatotropism, follow the same replication cycle, and have a nearly identical genetic organization.Hepadnaviral reverse transcription (34) occurs within cytoplasmic capsid particles. Reverse transcription begins with binding of P to an RNA stem-loop (ε) on the pregenomic RNA, and then this complex is encapsidated. Reverse transcription is primed by P itself, so minus-strand DNA is covalently linked to P (36, 40). Complexes containing P and the viral nucleic acids must be dynamic because three strand transfers are required to produce the mature circular viral DNA (21,22,38,41).The binding of P to ε requires the active participation of a molecular chaperone complex (13). In vitro reconstitution studies with recombinant duck hepatitis B virus (DHBV) P revealed that P-ε binding requires HSP90, HSP70, HSP40, HSP23, and HOP (2,11,14), although under certain circumstances only HSC70 and HSP40 are necessary (3). Because chaperones mod...

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The VP22 protein of herpes simplex virus type 2 (HSV-2) is a major component of the virion tegument. Previous work with HSV-1 indicated that VP22 is phosphorylated during infection, and phosphorylation may play a role in modulating VP22 localization in infected cells. It is not clear, however, when phosphorylation occurs in infected cells or how it is regulated. Less is known about the synthesis and phosphorylation of HSV-2 VP22. To study the complete biosynthetic history of HSV-2 VP22, we generated a monoclonal antibody to the carboxy terminus of VP22. Using immunoprecipitation and Western blot analyses, we show that HSV-2 VP22 can be found in three distinct isoforms in infected cells, two of which are phosphorylated. Like HSV-1 VP22, HSV-2 VP22 is synthesized ca. 4 h after infection, and the isoform later incorporated into virions is hypophosphorylated. In addition, we demonstrate for the first time (i) that newly synthesized VP22 is phosphorylated rapidly after synthesis, (ii) that this phosphorylation occurs in a virus-dependent manner, (iii) that the HSV-2 kinase UL13 is capable of inducing phosphorylation of VP22 in the absence of other viral proteins, (iv) that phosphorylated VP22 is very stable in infected cells, (v) that phosphorylated isoforms of VP22 are gradually dephosphorylated late in infection to produce the virion tegument form, and (vi) that this dephosphorylation occurs independently of viral DNA replication or virion assembly. These results indicate that HSV-2 VP22 is a stable protein that undergoes highly regulated, virus-dependent phosphorylation events in infected cells.The tegument of the herpesvirus virion is an amorphous structure that lies between the capsid and the envelope. The function of this subvirion structure appears to be twofold: to link the capsid of the newly forming viral particle with the envelope and to introduce regulatory proteins into a newly infected cell. The capacity of herpes simplex virus type 1 (HSV-1) and HSV-2 tegument proteins to regulate viral gene expression and to subvert cellular functions has been the focus of considerable study. For example, it is known that the tegument proteins VP16 and vhs transactivate viral ␣ genes and degrade host and viral mRNAs, respectively (14,15,22). These and other tegument proteins help to create a cellular environment that is advantageous to virus replication. VP22 is an abundant HSV tegument protein that possesses the remarkable property of intercellular spread (5). VP22 also can associate with and stabilize microtubules (7), interact with the transactivating protein VP16 (6), and associate with chromatin (13, 23). Although the function(s) of VP22 has not been established, its properties suggest that VP22 must play an important role in the HSV life cycle.Posttranslational modification is a common mechanism to regulate protein localization and function. VP22 is a 300-amino-acid protein that has been shown in both HSV-1 and HSV-2 to be posttranslationally modified by phosphorylation (1,8,13,23). Phosphorylation of HSV-1 VP22...

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