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The mumps virus nucleocapsid mRNA sequence and homology among the Paramyxoviridae proteins
1Department of Virology, School of Medicine, Karolinska Institute, Stockholm, Sweden.
Abstract:
The nucleotide sequence of mumps virus nucleocapsid protein (NP) mRNA has been determined from two overlapping cDNA clones and confirmed by partial sequencing of the mRNA and the genome. The mRNA contains 1844 nucleotides excluding poly(A) and encodes a protein of 553 amino acids with a calculated molecular weight of 61,792. A comparison of the mumps virus nucleocapsid protein sequence with that of other paramyxoviruses revealed a moderate degree of homology (33.1%) with the Newcastle disease virus (NDV) only. The nucleocapsid proteins of all paramyxoviruses studied to date, excluding that of the genus pneumovirus, have a conserved sequence of six amino acids (Ser-Tyr-Ala-Met-Gly-Val) except that of NDV which has a mismatch of two amino acids (Ser-Phe-Ala-Met-Gly-Met) in that sequence. In addition, there is another conserved region of seven amino acids (Phe-Ala-Pro-Gly-X-Tyr-Pro) in the nucleocapsid proteins of mumps virus, Sendai virus and parainfluenza virus type 3. The nucleocapsid proteins of measles virus and canine distemper virus (CDV) also have this conserved region but with three conservative amino acid changes.
Insights
The mumps virus nucleocapsid protein (NP) mRNA sequence was determined, revealing moderate homology with Newcastle disease virus (NDV). Conserved amino acid sequences were identified across paramyxoviruses, aiding in understanding viral evolution.
Area of Science:
- Virology
- Molecular Biology
- Genomics
Background:
- The nucleocapsid protein (NP) is crucial for paramyxovirus replication.
- Understanding NP sequence variation aids in viral classification and evolutionary studies.
Purpose of the Study:
- To determine the complete nucleotide sequence of mumps virus NP mRNA.
- To compare the mumps virus NP sequence with other paramyxoviruses.
- To identify conserved amino acid regions within paramyxovirus NPs.
Main Methods:
- Determination of mRNA nucleotide sequence using cDNA cloning.
- Partial sequencing of mRNA and viral genome for confirmation.
- Bioinformatic analysis for sequence homology and conserved regions.
Main Results:
- The mumps virus NP mRNA sequence (1844 nucleotides) and protein (553 amino acids) were elucidated.
- Moderate sequence homology (33.1%) was found between mumps virus NP and Newcastle disease virus (NDV) NP.
- Two conserved amino acid regions were identified across various paramyxoviruses, with specific variations noted in NDV, measles virus, and canine distemper virus (CDV).
Conclusions:
- The determined mumps virus NP sequence provides a basis for further molecular studies.
- Sequence comparisons highlight evolutionary relationships and conserved functional domains within the Paramyxoviridae family.
- Identified conserved regions may be critical for NP function and could serve as targets for antiviral strategies.