id	author	title	date	pages	extension	mime	words	sentences	flesch	summary	cache	txt
cord-269720-o81j3d1j	Page, Kevin W.	Sequence analysis of the leader RNA of two porcine coronaviruses: Transmissible gastroenteritis virus and porcine respiratory coronavirus	1990		.txt	text/plain	3553	172	59	Primer extension, of a synthetic oligonucleotide complementary to the 5′ end of the nucleoprotein gene of TGEV was used to produce a single-stranded DNA copy of the leader RNA from the nucleoprotein mRNA species from TGEV and PRCV, the sequences of which were determined by Maxam and Gilbert cleavage. Comparison of the leader RNAs of TGEV and PRCV with published leader RNAs of other coronaviruses was used to identify areas of conserved sequence and potential secondary structure that may be involved in the transcription of coronavirus subgenomic mRNA species. The site, ACTAAAC, is seven nucleotides upstream of the nucleoprotein initiation codon and has also been found to precede all the TGEV structural protein genes and two of the three potential genes shown to be at the 5' end of mRNA species (15) (16) (17) . The two porcine coronavirus leader sequences were identical, indicating that the two viruses probably use the same RNA polymerase-leader complex binding site, ACTAAAC, for the synthesis of subgenomic mRNA species.	./cache/cord-269720-o81j3d1j.txt	./txt/cord-269720-o81j3d1j.txt