Table 1. Examples of viral IRES elements.

Virus Family	Virus	Known ITAFs
DNA viruses
Herpesvirus	Kaposi-sarcoma-associated herpesvirus (KSHV)
Polyomavirus	Simian vacuolating virus 40 (SV40)
Nimavirus	White spot syndrome virus (WSSV)
RNA viruses
Picornaviruses	Poliovirus (PV)	PTB, PCBP2, PCBP1, La, unr SRp20
	Coxsackievirus B3 (CVB3)	PCBP2, La
	Enterovirus 71 (EV71)
	Hepatitis A virus (HAV)	PTB, PCBP2
	Human rhinovirus (HRV)	PTB, PCBP2, La, unr hnRNP A1
	Foot-and-mouth disease virus (FMDV)	PTB, ITAF45, La
	Encephalomyocarditis cirus (EMCV)	PTB, La
	Theiler’s murine encephalomyelitis virus (TMEV)	PTB
	Porcine teschovirus serotype 1 (PTV-1)
Potyviruses	Cowpea mosaic virus (CPMV) Tobacco etch virus (TEV)
Flaviviruses	Hepatitis C virus (HCV)	PTB, PCBP2, La, hnRNP D, hnRNP L
	Bovine viral diarrhea virus (BVDV) Classical swine fever virus (CSFV)
Dicistroviruses	Cricket paralysis virus (CrPV) Drosophila C virus (DCV) Plautia stali intestine virus (PSIV)
Retroviruses	Human T-call lymphotropic virus 1 (HTLV-1)	PTB, La
	Moloney murine leukenia virus (MoMuLV) Rous sarcoma virus (RSV) Simian immunodeficiency virus (SIV)
	Human immunodeficiency virus type 1 (HIV)	La

Some of the IRES elements identified in viral RNAs are shown, separated into DNA and RNA viruses, and including the virus family. Also shown are the known cellular IRES trans-acting factors (ITAFs) that function in translation for each particular viral IRES. Note that only non-canonical ITAFs are listed; this list does not include any canonical eukaryotic translation initiation factors (eIFs). Data compiled from [82,112,131,132].