Feline morbillivirus (FeMV) is a new emerging virus of domestic cats categorized under the genus of (Morbillivirus, associated with chronic kidney disease (CKD). The origin of the virus is yet to be determined, and whether it is caused by a spill-over event from wildlife or domestic cats remains speculative. Recombination event has been reported in FeMV isolate found in Japan; therefore, characterization of FeMV strains isolated in Malaysia (i.e., FeMV-Malaysia isolates) may provide some insight, thus adding some information on the viral evolution of FeMV. Therefore, this study aims to conduct a phylogenetic analysis and assess any genetic changes in the N gene of FeMV-Malaysia isolates. Through sequencing of N gene of seven isolates using three overlapping primer sets, the sequences spanning approximately 1.5kb of FeMV-N gene were obtained. DNA sequencing, nucleotide sequences, amino acid residues alignments, and phylogenetic analysis were performed. A nucleotide sequence alignment was also performed to compare the isolates obtained from two previous studies. From the alignment mentioned above, there were 19 variable sites of which there were absence of amino acid changes except for isolate UPM210 at position 806 and isolate UPM315 at position 823. Furthermore, protein alignment was done to compare FeMV-Malaysia isolates with FeMV strains from other countries, along with other morbillivirus-related isolates. From one of the conserved regions located within the N gene, similar amino acid sequences were detected across different morbilliviruses. Lastly, from the phylogenetic tree, it was illustrated that all partial FeMV-N gene Malaysia isolates sequenced in this study were clustered together in the same clade whereby these FeMV-N genes Malaysia isolates shared a common ancestor with isolates from Japan (SS3, MiJP003, ChJP073) and Thailand (Thai-U16, CTL16. CTL43).

• Communie, G., Ruigrok, R. W., Jensen, M. R., & Blackledge, M. (2014). Intrinsically disordered proteins implicated in paramyxoviral replication machinery. Current Opinion in Virology, 5(1), 72-81. https://doi.org/10.1016/j.coviro.2014.02.001

• de Luca, E., Sautto, G. A., Crisi, P. E., & Lorusso, A. (2021). Feline morbillivirus infection in domestic cats: What have we learned so far?. Viruses, 13(4), 683. https://doi.org/10.3390/v13040683

• Fleischmann, W. R. (1996). Viral genetics. In S. Baron (Ed.), Medical microbiology (4th ed., p. 43). University of Texas Medical Branch.

• Makhtar, S. T., Tan, S. W., Nasruddin, N. A., Abdul Aziz, N. A., Omar, A. R., & Mustaffa-Kamal, F. (2021). Development of TaqMan-based real-time RT-PCR assay based on N gene for the quantitative detection of feline morbillivirus. BMC Veterinary Research, 17(1), 128. https://doi.org/10.1186/s12917-021-02837-6

• Mohd Isa, N. H., Selvarajah, G. T., Khor, K. H., Tan, S. W., Manoraj, H., Omar, N. H., Omar, A. R., & Mustaffa-Kamal, F. (2019). Molecular detection and characterisation of feline morbillivirus in domestic cats in Malaysia. Veterinary Microbiology, 236, 108382-108382. https://doi.org/10.1016/j.vetmic.2019.08.005

• Morgan, E. M. (1991). Evolutionary relationships of Paramyxovirus nucleocapsid-associated proteins. In D. W. Kingsbury (Ed.), The Paramyxoviruses (pp. 163-179). Springer. https://doi.org/10.1007/978-1-4615-3790-8_5

• Park, E. S., Suzuki, M., Kimura, M., Maruyama, K., Mizutani, H., Saito, R., Kubota, N., Furuya, T., Mizutani, T., Imaoka, K., & Morikawa, S. (2014). Identification of a natural recombination in the F and H genes of feline morbillivirus. Virology, 468-470, 524-531. https://doi.org/10.1016/j.virol.2014.09.003

• Rima, B., Balkema-Buschmann, A., Dundon, W. G., Duprex, P., Easton, A., Fouchier, R., Kurath, G., Lamb, R., Lee, B., Rota, P., Wang, L., & Ictv Report, C. (2019). ICTV virus taxonomy profile: Paramyxoviridae. Journal of General Virology, 100(12), 1593-1594. https://doi.org/10.1099/jgv.0.001328

• Sakaguchi, S., Nakagawa, S., Yoshikawa, R., Kuwahara, C., Hagiwara, H., Asai, K. I., Kawakami, K., Yamamoto, Y., Ogawa, M., & Miyazawa, T. (2014). Genetic diversity of feline morbilliviruses isolated in Japan. Journal of General Virology, 95(7), 1464-1468. https://doi.org/10.1099/vir.0.065029-0

• Sieg, M., Busch, J., Eschke, M., Böttcher, D., Heenemann, K., Vahlenkamp, A., Reinert, A., Seeger, J., Heilmann, R., Scheffler, K., & Vahlenkamp, T. W. (2019). A new genotype of feline morbillivirus infects primary cells of the lung, kidney, brain and peripheral blood. Viruses, 11(2), 146. https://doi.org/10.3390/v11020146

• Sourimant, J., & Plemper, R. K. (2016). Organization, function, and therapeutic targeting of the morbillivirus RNA-dependent RNA polymerase complex. Viruses, 8(9), 251. https://doi.org/10.3390/v8090251

• Thakkar, V. D., Cox, R. M., Sawatsky, B., da Fontoura Budaszewski, R., Sourimant, J., Wabbel, K., Makhsous, N., Greninger, A. L., von Messling, V., & Plemper, R. K. (2018). The unstructured paramyxovirus nucleocapsid protein tail domain modulates viral pathogenesis through regulation of transcriptase activity. Journal of Virology, 92(8), e02064-17. https://doi.org/10.1128/jvi.02064-17

• Woo, P. C., Lau, S. K., Wong, B. H., Fan, R. Y., Wong, A. Y., Zhang, A. J., Wu, Y., Choi, G. K., Li, K. S., Hui, J., Wang, M., Zheng, B. J., Chan, K. H., & Yuen, K. Y. (2012). Feline morbillivirus, a previously undescribed paramyxovirus associated with tubulointerstitial nephritis in domestic cats. Proceedings of the National Academy of Sciences of the United States of America, 109(14), 5435-5440. https://doi.org/10.1073/pnas.1119972109

• Wu, X., Lu, Y., Zhou, S., Chen, L., & Xu, B. (2016). Impact of climate change on human infectious diseases: Empirical evidence and human adaptation. Environment International, 86, 14-23. https://doi.org/10.1016/j.envint.2015.09.007