ORIGINAL ARTICLE
Methyl-beta cyclodextrin alters the production and infectivity
of Sendai virus
Hiroshi Fujita
•
Katsuto Tamai
•
Masako Kawachi
•
Kotaro Saga
•
Takashi Shimbo
•
Takehiko Yamazaki
•
Yasufumi Kaneda
Received: 5 August 2010 / Accepted: 22 January 2011 / Published online: 11 February 2011
Ó Springer-Verlag 2011
Abstract Cellular membrane cholesterol has been shown
to support various membrane proteins. However, the role
and function of membrane cholesterol in viral production
are still unclear. Here, we investigated the effects of cho-
lesterol depletion from the cell membrane on the produc-
tion of hemagglutinating virus of Japan (HVJ; Sendai
virus). Cholesterol depletion from LLC-MK2 cells by
methyl-beta cyclodextrin treatment resulted in a marked
increase in the production of both HVJ from the infected
cells and virus-like particles from M-gene-transfected cells.
The HVJ produced from cholesterol-depleted cells pos-
sessed a reduced amount of envelope cholesterol and
showed a rather wide range of particle sizes and amount of
envelope protein compared to HVJ produced from
untreated cells. Direct depletion of envelope cholesterol
from HVJ significantly impaired its infectivity, even
without a change in envelope protein composition. These
results suggest that membrane cholesterol plays important
roles in regulating the production of infectious HVJ.
Introduction
Cholesterol-rich microdomains on the cell membrane,
called lipid rafts, have been shown to function in regulating
the production of various viruses [4]. However, cholesterol
depletion from infected cells affects the production of each
virus differently. A recent study reported that cholesterol
depletion from the cell membrane promotes the budding of
influenza virus [3]. Because the hemagglutinin and neur-
aminidase glycoproteins of influenza virus have an intrinsic
affinity for lipid rafts, cholesterol depletion has been sug-
gested to release raft-trapped hemagglutinin and neur-
aminidase to be dispersed on the cell surface and to
accelerate budding of virions [20, 32, 38]. Measles virus
has also been shown to bud in places other than choles-
terol-rich regions of cells [22]. However, in the case of
Semliki Forest virus, membrane cholesterol depletion has
been shown to dramatically reduce viral production [21].
Production of human immunodeficiency virus-1 is also
significantly reduced by cholesterol depletion in cells
expressing Gag protein [23, 27, 28].
Hemagglutinating virus of Japan (HVJ), also called
Sendai virus, belongs to the genus Respirovirus of the
family Paramyxoviridae. The genome of HVJ is a linear
and non-segmented negative-strand RNA of approximately
15.4 kb, containing six major genes that are arranged in
tandem. This genome is tightly encapsulated with nucleo-
protein and is further complexed to phosphoprotein and
large protein (L protein). This ribonucleoprotein complex
constitutes the internal core structure of the virion. The
viral envelope contains two spike proteins: hemagglutinin-
neuraminidase (HN) protein, which mediates the attach-
ment of virions, and fusion (F) protein, which mediates the
penetration of ribonucleoproteins into the infected cells.
The M protein functions in virus assembly and budding [6].
HVJ infects and replicates independently of cellular
nuclear functions and without reverse transcription during
its life cycle in most mammalian cells, which is beneficial
for analysis of factors related to virus production, such
as membrane cholesterol [17]. A previous study demon-
strated that cholesterol depletion from the cell membrane
increases the proportion of M protein in the HVJ protein
H. Fujita Á K. Tamai Á M. Kawachi Á K. Saga Á T. Shimbo Á
T. Yamazaki Á Y. Kaneda (&)
Division of Gene Therapy Science, Graduate School
of Medicine, Osaka University, 2-2 Yamadaoka,
Suita, Osaka 565-0871, Japan
e-mail: kaneday@gts.med.osaka-u.ac.jp
123
Arch Virol (2011) 156:995–1005
DOI 10.1007/s00705-011-0938-7