Infectious rotavirus enters cells by direct cell membrane penetration, not by endocytosis

Journal Article · Fri Apr 01 00:00:00 EST 1988 · Journal of Virology; (USA)

OSTI ID:6522780

Kaljot, K T; Shaw, R D; Greenberg, H B ^[1]; Rubin, D H ^[2]

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1. Stanford Univ. School of Medicine, CA (USA) Palo Alto Veterans Administration Medical Center, CA (USA)
2. Univ. of Pennsylvania, Philadelphia (USA)

Rotaviruses are icosahedral viruses with a segmented, double-stranded RNA genome. They are the major cause of severe infantile infectious diarrhea. Rotavirus growth in tissue culture is markedly enhanced by pretreatment of virus with trypsin. Trypsin activation is associated with cleavage of the viral hemagglutinin (viral protein 3 (VP3); 88 kilodaltons) into two fragments (60 and 28 kilodaltons). The mechanism by which proteolytic cleavage leads to enhanced growth is unknown. To determine whether trypsin treatment affected rotavirus internalization, the authors studied the kinetics of entry of infectious rhesus rotavirus (RRV) into MA104 cells. Trypsin-activated RRV was internalized with a half-time of 3 to 5 min, while nonactivated virus disappeared from the cell surface with a half-time of 30 to 50 min. In contrast to trypsin-activated RRV, loss of nonactivated RRV from the cell surface did not result in the appearance of infection, as measured by plaque formation. Purified trypsin-activated RRV added to cell monolayers at pH 7.4 mediated {sup 51}Cr, ({sup 14}C)choline, and ({sup 3}H)inositol released from prelabeled MA104 cells. This release could be specifically blocked by neutralizing antibodies to VP3. These results suggest that MA104 cell infection follows the rapid entry of trypsin-activated RRV by direct cell membrane penetration. Cell membrane penetration of infectious RRV is initiated by trypsin cleavage of VP3. Neutralizing antibodies can inhibit this direct membrane penetration.

• OSTI ID: 6522780
• Journal Information: Journal of Virology; (USA), Vol. 62:4; ISSN 0022-538X
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
PROTEINS
ENZYMATIC HYDROLYSIS
TRYPSIN
BIOLOGICAL EFFECTS
VIRUSES
UPTAKE
CARBON 14 COMPOUNDS
CELL CULTURES
CELL MEMBRANES
CHOLINE
CHROMIUM 51
DIARRHEA
INOSITOL
RNA
TRITIUM COMPOUNDS
VIRAL DISEASES
ALCOHOLS
AMINES
AMMONIUM COMPOUNDS
BETA DECAY RADIOISOTOPES
CARBOHYDRATES
CELL CONSTITUENTS
CHEMICAL REACTIONS
CHROMIUM ISOTOPES
DECOMPOSITION
DISEASES
DRUGS
ELECTRON CAPTURE RADIOISOTOPES
ENZYMES
EVEN-ODD NUCLEI
HYDROGEN COMPOUNDS
HYDROLASES
HYDROLYSIS
HYDROXY COMPOUNDS
INFECTIOUS DISEASES
INOSITOLS
INTERMEDIATE MASS NUCLEI
ISOTOPES
LABELLED COMPOUNDS
LIPOTROPIC FACTORS
LYSIS
MEMBRANES
MICROORGANISMS
MONOSACCHARIDES
NUCLEI
NUCLEIC ACIDS
ORGANIC COMPOUNDS
PARASITES
PEPTIDE HYDROLASES
QUATERNARY COMPOUNDS
RADIOISOTOPES
SACCHARIDES
SERINE PROTEINASES
SOLVOLYSIS
SYMPTOMS
550701* - Microbiology- Tracer Techniques