Journal of General Virology, Vol 79, 1189-1195, Copyright © 1998 by Society for General Microbiology

ARTICLES

A conserved African swine fever virus right variable region gene, l11L, is non-essential for growth in vitro and virulence in domestic swine

SB Kleiboeker, GF Kutish, JG Neilan, Z Lu, L Zsak and DL Rock
Plum Island Animal Disease Center, Agricultural Research Service, U.S. Department of Agriculture, Greenport, NY 11944-0848, USA.

The right variable region of the African swine fever virus (ASFV) genome is known to contain genes with functions involving virus virulence and host range in swine. A novel open reading frame, ORF l11L, which was absent in the non-pathogenic, cell culture-adapted European isolate BA71V, was identified in the pathogenic African isolate Malawi Lil-20/1. The location of l11L in the right variable region, together with its absence in BA71V, suggested that l11L may have a function in virus virulence and/or host range. Here, we show that the l11L gene is highly conserved among pathogenic African, European and Caribbean ASFV field isolates and that it exists either in a short form, encoding a protein of 77-78 amino acids (9.1 kDa) or in a longer form of 93-94 amino acids (11.1 kDa). The presence of two predicted membrane-spanning segments suggests that l11L is an integral membrane protein. RT-PCR analysis demonstrated that l11L mRNA is expressed late in the virus replication cycle. A recombinant l11L gene deletion mutant, deltal11L, was constructed from the ASFV isolate Malawi Lil-20/1 to examine gene function. Deletion of l11L did not affect virus replication in swine macrophage cell cultures nor virulence in domestic pigs, indicating that l11L is non-essential for growth in vitro and for virus virulence in domestic swine.

This article has been cited by other articles:

				L. Zsak, M. V. Borca, G. R. Risatti, A. Zsak, R. A. French, Z. Lu, G. F. Kutish, J. G. Neilan, J. D. Callahan, W. M. Nelson, et al. Preclinical Diagnosis of African Swine Fever in Contact-Exposed Swine by a Real-Time PCR Assay J. Clin. Microbiol., January 1, 2005; 43(1): 112 - 119. [Abstract] [Full Text] [PDF]

				J. G. Neilan, L. Zsak, Z. Lu, G. F. Kutish, C. L. Afonso, and D. L. Rock Novel Swine Virulence Determinant in the Left Variable Region of the African Swine Fever Virus Genome J. Virol., March 7, 2002; 76(7): 3095 - 3104. [Abstract] [Full Text] [PDF]

				L. Zsak, Z. Lu, T. G. Burrage, J. G. Neilan, G. F. Kutish, D. M. Moore, and D. L. Rock African Swine Fever Virus Multigene Family 360 and 530 Genes Are Novel Macrophage Host Range Determinants J. Virol., April 1, 2001; 75(7): 3066 - 3076. [Abstract] [Full Text]

				T. Lewis, L. Zsak, T. G. Burrage, Z. Lu, G. F. Kutish, J. G. Neilan, and D. L. Rock An African Swine Fever Virus ERV1-ALR Homologue, 9GL, Affects Virion Maturation and Viral Growth in Macrophages and Viral Virulence in Swine J. Virol., February 1, 2000; 74(3): 1275 - 1285. [Abstract] [Full Text]

				S. B. Kleiboeker, G. A. Scoles, T. G. Burrage, and J.-H. Sur African Swine Fever Virus Replication in the Midgut Epithelium Is Required for Infection of Ornithodoros Ticks J. Virol., October 1, 1999; 73(10): 8587 - 8598. [Abstract] [Full Text] [PDF]

				J. G. Neilan, M. V. Borca, Z. Lu, G. F. Kutish, S. B. Kleiboeker, C. Carrillo, L. Zsak, and D. L. Rock An African swine fever virus ORF with similarity to C-type lectins is non-essential for growth in swine macrophages in vitro and for virus virulence in domestic swine J. Gen. Virol., October 1, 1999; 80(10): 2693 - 2697. [Abstract] [Full Text]