The third open reading frame (ORF3) located at the 3 end of the genomic RNA of feline calicivirus (FCV) encodes a small (12.2-kDa) minor structural protein of 106 amino acids designated VP2. Point mutations and deletions were introduced into an infectious FCV cDNA clone in order to evaluate the functional importance of ORF3 and its encoded protein, VP2. Deletion of the entire ORF3 sequence was lethal for the virus, and evidence was found for strong selective pressure to produce the VP2 protein. Extended deletions in the 5 end and small deletions in the 3 end of ORF3, as well as the introduction of stop codons into the ORF3 sequence, were tolerated by the viral replication machinery, but infectious virus could not be recovered. Infectious virus particles could be rescued from a full-length FCV cDNA clone encoding a nonfunctional VP2 when VP2 was provided in trans from a eukaryotic expression plasmid. Our data indicate that VP2, a protein apparently unique to the caliciviruses, is essential for productive replication that results in the synthesis and maturation of infectious virions and that the ORF3 nucleotide sequence itself overlaps a cis-acting RNA signal at the genomic 3 end.Caliciviruses are small, nonenveloped, positive-strand RNA viruses that infect a broad range of hosts. Their virions are 27 to 40 nm in diameter and have icosahedral symmetry. The virion capsid is comprised of 180 copies of the major structural protein, VP1 (29, 31), and a minor structural protein designated VP2 (7,27,38,43). The capsid surrounds the VPg-linked polyadenylated RNA genome (2,6,14,23), and in at least two caliciviruses, rabbit hemorrhagic disease virus (RHDV) and feline calicivirus (FCV), a VPg-linked ϳ2.2-to 2.6-kb subgenomic-size RNA is also packaged into virions (23,25). The RNA genomes of caliciviruses range in size from 7.3 to 8.3 kb and are organized into either two or three major open reading frames (ORFs) (9). In the genera Lagovirus and Sapovirus of the family Caliciviridae, the nonstructural proteins and the structural protein VP1 are encoded in the same ORF. In the genera Vesivirus and Norovirus, VP1 is encoded in a separate ORF. In all genera, a genomic-length RNA serves as a template for synthesis of the nonstructural polyprotein while the 2.2-to 2.6-kb bicistronic subgenomic RNA is used for translation of the VP1 and VP2 proteins (3,26,28).All caliciviruses encode the VP2 protein in a separate ORF near the 3Ј end of the genome (ORF3 for noroviruses and vesiviruses and ORF2 for sapoviruses and lagoviruses). Comparative sequence analyses of this terminal ORF and the deduced VP2 amino acid sequence indicate that this region of the genome is highly variable in sequence between genera, with as little as 10% amino acid similarity. In addition, these proteins show significant variation in length, ranging from 106 (FCV) to 268 (norovirus MD-145) amino acids (aa). The expression of VP2 in calicivirus-infected cells has been reported for FCV and RHDV (13,17,42). For FCV, the level of VP2 expression has been estimated to ...
Despite cosmetic procedures being on the rise in the US in all demographics, cosmetic procedures remain heavily skewed towards non-skin of color patients. Cosmetic clinical trials in the United States must be representative of the everincreasing diversity of the US population. We sought to analyze published cosmetic randomized controlled trials, both industry-sponsored and investigatorinitiated, to characterize and assess representation of skin of color participants over the past three decades. Our study shows that industry sponsorship correlates with poor study participant ethnic/racial diversity in aesthetic randomized controlled trials, and should serve as a call to action for industries to increase the inclusion of skin of color participants in their studies.
Hair transplantation is a safe well-tolerated procedure to improve hair loss in African American women with end-stage CCCA who histologically display a lack of inflammation on scalp biopsy.
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