Evolution of the 5′-end of genomic rna of murine coronaviruses during passages in vitro

Shinji Makino, Michael M C Lai

Research output: Contribution to journalArticle

36 Citations (Scopus)

Abstract

The 5′-ends of the genomic RNA and subgenomic mRNAs of murine coronavirus (MHV) have a stretch of approximately 70 nucleotides of leader sequences. The 3'-region of this leader sequence contains several repeats of a pentanucleotide (UCUAA), whose number varies among different MHV strains. It has been demonstrated that this UCUAA repeat plays crucial roles in the discontinuous transcription of MHV mRNAs. In the present study, we demonstrate that the number of UCUAA repeats in the leader sequence of MHV genome rapidly decreases during serial passages of viruses on susceptible cells. The downward evolution of the number of UCUAA repeats was not due to a higher growth rate of the viruses with fewer repeats, but seemed to be due to homologous interference between viruses with different numbers of UCUAA repeat. The ease with which these variant viruses arose suggests the high frequency of the occurrence of this deletion during RNA replication. This finding is in agreement with the proposed discontinuous and nonprocessive mode of coronavirus RNA synthesis. Analysis of the intracellular subgenomic mRNA species of viruses with different numbers of UCUAA repeats and of MHV recombinant viruses suggests that the number of this pentanucleotide repeat at the 3′-end of the leader sequence may regulate the synthesis of certain mRNA species, in agreement with the leader-primed transcription mechanism.

Original languageEnglish (US)
Pages (from-to)227-232
Number of pages6
JournalVirology
Volume169
Issue number1
DOIs
StatePublished - 1989
Externally publishedYes

Fingerprint

Coronavirus
RNA
Viruses
Messenger RNA
Microsatellite Repeats
Serial Passage
In Vitro Techniques
Genome
Growth

ASJC Scopus subject areas

  • Virology
  • Infectious Diseases

Cite this

Evolution of the 5′-end of genomic rna of murine coronaviruses during passages in vitro. / Makino, Shinji; Lai, Michael M C.

In: Virology, Vol. 169, No. 1, 1989, p. 227-232.

Research output: Contribution to journalArticle

@article{1bc481e9b9c449b4a6cc0bf38807113e,
title = "Evolution of the 5′-end of genomic rna of murine coronaviruses during passages in vitro",
abstract = "The 5′-ends of the genomic RNA and subgenomic mRNAs of murine coronavirus (MHV) have a stretch of approximately 70 nucleotides of leader sequences. The 3'-region of this leader sequence contains several repeats of a pentanucleotide (UCUAA), whose number varies among different MHV strains. It has been demonstrated that this UCUAA repeat plays crucial roles in the discontinuous transcription of MHV mRNAs. In the present study, we demonstrate that the number of UCUAA repeats in the leader sequence of MHV genome rapidly decreases during serial passages of viruses on susceptible cells. The downward evolution of the number of UCUAA repeats was not due to a higher growth rate of the viruses with fewer repeats, but seemed to be due to homologous interference between viruses with different numbers of UCUAA repeat. The ease with which these variant viruses arose suggests the high frequency of the occurrence of this deletion during RNA replication. This finding is in agreement with the proposed discontinuous and nonprocessive mode of coronavirus RNA synthesis. Analysis of the intracellular subgenomic mRNA species of viruses with different numbers of UCUAA repeats and of MHV recombinant viruses suggests that the number of this pentanucleotide repeat at the 3′-end of the leader sequence may regulate the synthesis of certain mRNA species, in agreement with the leader-primed transcription mechanism.",
author = "Shinji Makino and Lai, {Michael M C}",
year = "1989",
doi = "10.1016/0042-6822(89)90060-3",
language = "English (US)",
volume = "169",
pages = "227--232",
journal = "Virology",
issn = "0042-6822",
publisher = "Academic Press Inc.",
number = "1",

}

TY - JOUR

T1 - Evolution of the 5′-end of genomic rna of murine coronaviruses during passages in vitro

AU - Makino, Shinji

AU - Lai, Michael M C

PY - 1989

Y1 - 1989

N2 - The 5′-ends of the genomic RNA and subgenomic mRNAs of murine coronavirus (MHV) have a stretch of approximately 70 nucleotides of leader sequences. The 3'-region of this leader sequence contains several repeats of a pentanucleotide (UCUAA), whose number varies among different MHV strains. It has been demonstrated that this UCUAA repeat plays crucial roles in the discontinuous transcription of MHV mRNAs. In the present study, we demonstrate that the number of UCUAA repeats in the leader sequence of MHV genome rapidly decreases during serial passages of viruses on susceptible cells. The downward evolution of the number of UCUAA repeats was not due to a higher growth rate of the viruses with fewer repeats, but seemed to be due to homologous interference between viruses with different numbers of UCUAA repeat. The ease with which these variant viruses arose suggests the high frequency of the occurrence of this deletion during RNA replication. This finding is in agreement with the proposed discontinuous and nonprocessive mode of coronavirus RNA synthesis. Analysis of the intracellular subgenomic mRNA species of viruses with different numbers of UCUAA repeats and of MHV recombinant viruses suggests that the number of this pentanucleotide repeat at the 3′-end of the leader sequence may regulate the synthesis of certain mRNA species, in agreement with the leader-primed transcription mechanism.

AB - The 5′-ends of the genomic RNA and subgenomic mRNAs of murine coronavirus (MHV) have a stretch of approximately 70 nucleotides of leader sequences. The 3'-region of this leader sequence contains several repeats of a pentanucleotide (UCUAA), whose number varies among different MHV strains. It has been demonstrated that this UCUAA repeat plays crucial roles in the discontinuous transcription of MHV mRNAs. In the present study, we demonstrate that the number of UCUAA repeats in the leader sequence of MHV genome rapidly decreases during serial passages of viruses on susceptible cells. The downward evolution of the number of UCUAA repeats was not due to a higher growth rate of the viruses with fewer repeats, but seemed to be due to homologous interference between viruses with different numbers of UCUAA repeat. The ease with which these variant viruses arose suggests the high frequency of the occurrence of this deletion during RNA replication. This finding is in agreement with the proposed discontinuous and nonprocessive mode of coronavirus RNA synthesis. Analysis of the intracellular subgenomic mRNA species of viruses with different numbers of UCUAA repeats and of MHV recombinant viruses suggests that the number of this pentanucleotide repeat at the 3′-end of the leader sequence may regulate the synthesis of certain mRNA species, in agreement with the leader-primed transcription mechanism.

UR - http://www.scopus.com/inward/record.url?scp=0024543970&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0024543970&partnerID=8YFLogxK

U2 - 10.1016/0042-6822(89)90060-3

DO - 10.1016/0042-6822(89)90060-3

M3 - Article

C2 - 2538033

AN - SCOPUS:0024543970

VL - 169

SP - 227

EP - 232

JO - Virology

JF - Virology

SN - 0042-6822

IS - 1

ER -