RT Journal Article SR Electronic(1) A1 Frisby, D. P. A1 Cotter, Rosalind I. A1 Richards, B. M.YR 1977 T1 Structural Studies of Encephalomyocarditis Virus RNA both in situ and in Free Solution JF Journal of General Virology, VO 37 IS 2 SP 311 OP 322 DO https://doi.org/10.1099/0022-1317-37-2-311 PB Microbiology Society, SN 1465-2099, AB Summary The secondary structure of encephalomyocarditis (EMC) virus RNA has been studied in situ and in free solution by absorbance-temperature relationships and by circular dichroism (CD). Extracted EMC virus RNA melts reversibly and has a hypochromicity of about 20%; analysis of CD spectra and formaldehyde treatment suggests that approx. 60% of the nucleotides are involved in base-pairing at 25 °C. It is shown that the RNA within the virus particle is less structured than when it exists in free solution, being partially stabilized by capsid protein against melting until the virion is disrupted to release the intact RNA. Upon clarification to remove denatured capsid protein, the released RNA gives a melting profile identical with that of phenol-extracted virus RNA. The results suggest that the intact structure of the virus is dependent upon intimate non-covalent bonds between RNA and protein together with hydrophobic bonds between the protein subunits., UL https://www.microbiologyresearch.org/content/journal/jgv/10.1099/0022-1317-37-2-311