RASCAL is a new human cytomegalovirus-encoded protein that localizes to the nuclear lamina and in cytoplasmic vesicles at late times postinfection.
The products of numerous open reading frames (ORFs) present in the genome of human cytomegalovirus (CMV) have not been characterized. Here, we describe the identification of a new CMV protein localizing to the nuclear envelope and in cytoplasmic vesicles at late times postinfection. Based on this distinctive localization pattern, we called this new protein nuclear rim-associated cytomegaloviral protein, or RASCAL. Two RASCAL isoforms exist, a short version of 97 amino acids encoded by the majority of CMV strains and a longer version of 176 amino acids encoded by the Towne, Toledo, HAN20, and HAN38 strains. Both isoforms colocalize with lamin B in deep intranuclear invaginations of the inner nuclear membrane (INM) and in novel cytoplasmic vesicular structures possibly derived from the nuclear envelope. INM infoldings have been previously described as sites of nucleocapsid egress, which is mediated by the localized disruption of the nuclear lamina, promoted by the activities of viral and cellular kinases recruited by the lamina-associated proteins UL50 and UL53. RASCAL accumulation at the nuclear membrane required the presence of UL50 but not of UL53. RASCAL and UL50 also appeared to specifically interact, suggesting that RASCAL is a new component of the nuclear egress complex (NEC) and possibly involved in mediating nucleocapsid egress from the nucleus. Finally, the presence of RASCAL within cytoplasmic vesicles raises the intriguing possibility that this protein might participate in additional steps of virion maturation occurring after capsid release from the nucleus.
Miller
Matthew S
MS
Department of Microbiology and Immunology, Schulich School of Medicine and Dentistry, the University of Western Ontario, London, Ontario N6A 5C1, Canada.
Furlong
Wendy E
WE
Pennell
Leesa
L
Geadah
Marc
M
Hertel
Laura
L
D000595:Amino Acid Sequence; D002460:Cell Line; D003587:Cytomegalovirus / Q000502:physiology*; D022162:Cytoplasmic Vesicles / Q000737:chemistry*; D006801:Humans; D008969:Molecular Sequence Data; D034881:Nuclear Lamina / Q000737:chemistry*; D025941:Protein Interaction Mapping; D020033:Protein Isoforms / Q000032:analysis; D016415:Sequence Alignment; D014764:Viral Proteins / Q000032:analysis*; D057074:Virus Release
D020033:Protein Isoforms; D014764:Viral Proteins
J Mol Biol. 1982 May 5;157(1):105-32
7108955
Rev Med Virol. 2010 Jul;20(4):214-30
20069615
Curr Top Microbiol Immunol. 2008;325:63-83
18637500
Arch Virol. 1991;117(3-4):143-64
1850227
J Virol. 2009 Apr;83(7):2996-3006
19153235
J Submicrosc Cytol Pathol. 2000 Jan;32(1):17-45
10877101
J Gen Virol. 1984 Nov;65 ( Pt 11):1979-90
6094712
Ann Intern Med. 1984 Oct;101(4):478-83
6089634
J Virol. 2002 Feb;76(4):1537-47
11799148
Lancet. 1974 Jan 5;1(7845):1-5
4128996
Nucleic Acids Res. 2004 Jul 1;32(Web Server issue):W414-9
15215421
Bioinformatics. 2001 Aug;17(8):721-8
11524373
Bioinformatics. 2007 Nov 1;23(21):2947-8
17846036
Proc Natl Acad Sci U S A. 2003 Nov 25;100(24):14223-8
14623981
Curr Top Microbiol Immunol. 2008;325:1-19
18637497
J Mol Biol. 2000 Jul 21;300(4):1005-16
10891285
Curr Top Microbiol Immunol. 2008;325:85-100
18637501
Proc Natl Acad Sci U S A. 2003 Oct 14;100(21):12396-401
14519856
J Virol. 2007 Oct;81(19):10792-803
17652388
J Virol. 2006 Jan;80(2):710-22
16378974
J Virol. 2009 Jul;83(14):7015-28
19403668
Comput Appl Biosci. 1994 Dec;10(6):685-6
7704669
Curr Top Microbiol Immunol. 2008;325:417-70
18637519
J Gen Virol. 2004 May;85(Pt 5):1301-1312
15105547
J Virol. 2007 Mar;81(6):3042-8
17192309
J Virol. 2008 Jan;82(1):60-70
17942555
J Gen Virol. 2009 Mar;90(Pt 3):579-590
19218202
Proteomics. 2004 Jun;4(6):1633-49
15174133
J Mol Biol. 2004 Jul 16;340(4):783-95
15223320
J Gen Virol. 2002 May;83(Pt 5):1005-1012
11961254
J Virol. 2007 Nov;81(22):12128-34
17855538
J Virol. 2005 Oct;79(19):12205-17
16160147
Protein Eng. 1997 Jun;10(6):673-6
9278280
J Gen Virol. 2008 Feb;89(Pt 2):359-368
18198366
Curr Top Microbiol Immunol. 1990;154:125-69
2161319
Science. 2002 Aug 2;297(5582):854-7
12161659
J Cell Mol Med. 2009 Jun;13(6):1059-85
19210577
J Biol Chem. 2005 Sep 30;280(39):33357-67
15975922
J Biol Chem. 2010 Apr 30;285(18):13979-89
20202933
J Virol. 2006 Feb;80(3):1191-203
16414996
Rev Med Virol. 2001 May-Jun;11(3):191-200
11376481
J Gen Virol. 2007 Oct;88(Pt 10):2642-2650
17872514
J Gen Virol. 2005 Feb;86(Pt 2):275-284
15659746
Virology. 1997 Dec 8;239(1):46-61
9426445
J Infect Dis. 2001 Oct 15;184(8):1078-81
11574926
J Virol. 2002 Sep;76(18):9551-5
12186938
Infect Immun. 1975 Sep;12(3):521-7
170203
J Virol. 2005 Aug;79(16):10330-8
16051825
J Biol Chem. 2005 Apr 15;280(15):14427-32
15647269
J Biol Chem. 1997 Aug 22;272(34):21274-80
9261138
J Gen Virol. 2003 Jan;84(Pt 1):17-28
12533697
J Virol. 1999 Jul;73(7):5757-66
10364327
Biotechniques. 1989 Oct;7(9):980-2, 984-6, 989-90
2631796
J Virol. 2003 Jul;77(13):7563-74
12805456
Am J Pathol. 1964 May;44:799-821
14155026
Arch Virol. 1988;98(1-2):51-64
2829797
Proc Soc Exp Biol Med. 1956 Jun;92(2):418-24
13350367
J Virol. 1996 Sep;70(9):6340-6
8709262
J Gen Virol. 2000 Feb;81(Pt 2):393-9
10644837
Virus Res. 2009 Aug;143(2):222-34
19651457
J Virol. 2004 Sep;78(18):10023-33
15331735
J Virol. 2004 Oct;78(20):10960-6
15452216
Autophagy. 2009 Oct;5(7):1026-9
19556870
Proc Natl Acad Sci U S A. 2005 Dec 13;102(50):18153-8
16319222
Proc Natl Acad Sci U S A. 2003 Dec 9;100(25):14976-81
14657367
Rev Med Virol. 2009 Jul;19(4):215-29
19434630
J Virol. 1996 Jan;70(1):78-83
8523595
J Infect Dis. 1989 May;159(5):860-5
2540247
J Gen Virol. 2008 Mar;89(Pt 3):731-740
18272765
PLoS Pathog. 2009 Jan;5(1):e1000275
19165338
J Virol. 2007 May;81(9):4429-37
17301149
J Virol. 1998 Apr;72(4):3321-9
9525659
J Virol. 2006 Jan;80(1):494-504
16352573