Disease relevance of L4

• The complete nucleotide sequence of the 5' noncoding region of the adenovirus 2 hexon messenger RNA has been established by sequence analysis of reverse transcripts [1].
• We found that less than half of the donors harbored a proliferating T(M) response directed against the CAV-2 virion (versus >85% against HAd5) in spite of a conserved antigenic Adenoviridae epitope in the CAV-2 hexon [2].
• This study has used the strategy of gene replacement to characterize the contribution of the adenovirus (Ad) capsid protein hexon to serotype definition [3].
• A variety of recombinant proteins derived from protein pVI of human adenovirus type 2 (Ad2) were analysed for their ability to bind Ad2 hexon in vitro [4].
• The putative hexon gene of a porcine adenovirus serotype 3 (PAV3) has been identified, cloned and the nucleotide sequence determined [5].

High impact information on L4

• The estimates are ambiguous, however, due to the presence of tandemly repeated sequences at both ends of the intervening sequence between the third leader segment and the body of the hexon mRNA [1].
• The mRNA shares a poly(A) addition site with the hexon and pVI mRNAs, and carries a leader sequence which is related, and probably identical, to the tripartite leader, found in late adenovirus mRNAs [6].
• The sequence revealed unexpectedly that the 3' non-coding region of the hexon mRNA contains a 609 nucleotide long uninterrupted translational reading frame following a potential initiator AUG. A late 14S mRNA, corresponding to the open reading frame, could be identified by S1 nuclease mapping and electronmicroscopy [6].
• In spite of the serotype distinctiveness of the chimeric hexon viruses, epitope similarity between the vectors resulted in a low level of cross-reactive neutralizing antibody, which in combination with activated cellular and innate arms of the immune system is sufficient to suppress gene transduction following readministration in vivo [3].
• The structure of the hexon trimer shows how economically it meets the demands of its function as a stable protective viral coat, reveals the significance of the special features in its unusual amino acid sequence, and explains its biochemical and immunological properties [7].

Biological context of L4

• (iii) A sequence with the composition (T)n (A)p (T)q (n, p, q greater than or equal to 1) is found 4 to 24 nucleotides beyond all the adenovirus-specific polyadenylation sites except the 3'-coterminal family L4 [8].
• Both polypeptides are encoded by the same translational reading frame, suggesting the evolution of pVI and hexon as separate proteins by the introduction of a termination codon and selection of a new splice acceptor site in an ancestral fused polypeptide chain [9].
• HindIII restriction fragments containing the hexon and other viral genes were cloned into the plasmids pUC19 and pBlueScript SK(-) and sequenced [10].
• Similar to other members of the genus Mastadenovirus the EAdV1 hexon yielded two highly conserved genome segments at the N- and C-termini which flanked intermediate variable and hypervariable regions [10].
• Based on sequence homology with human adenovirus 2 (HAdV2), the hexon gene of equine adenovirus 1 (EAdV1) was identified [10].

Anatomical context of L4

• For the investigation of epitope composition of different adenovirus hexon types sixty-one mouse ascitic fluids containing monoclonal antibodies (MAbs) developed in three different panels were used [11].

Associations of L4 with chemical compounds

• It has a density in cesium chloride of 1.339 g/ml and produces soluble components in human embryonic kidney culture that band at 1.303 g/ml (hexon), 1.283 g/ml (dodecon), and 1.212 g/ml (fiber), the last component being the only incomplete hemagglutinin found [12].

Other interactions of L4

• A possible candidate for such a factor is the L4-encoded 33K gene product, a protein conserved throughout the Mastadenoviridae, but of no known function [13].

Analytical, diagnostic and therapeutic context of L4

• Multiple sequence alignment with the other five known hexon protein sequences reveals an overall residue identity of 51% and residue conservation of 66% [14].
• Apparently, in the examined viruses, parts of the DNA sequence coding for the basal part of the hexon protein are conserved enough for being applicable in polymerase chain reaction (PCR) as primers [15].

References