“…Six of these genes appear to be required for DNA replication and encode the following proteins : a DNA polymerase homologue (Tomalski et al, 1988) ; P143, a helicase homologue (Lu & Carstens, 1991) that is capable of binding dsDNA (Laufs et al, 1997) ; LEF-3, a homotrimeric ssDNA-binding (SSB) protein Hang et al, 1995) that appears to be involved in transporting P143 into the nucleus (Wu & Carstens, 1998) ; IE-1, a transcriptional activator (Guarino & Summers, 1987) which also binds to hrs (Choi & Guarino, 1995 ;Guarino & Dong, 1991 ;Kovacs et al, 1992 ;Leisy et al, 1995 ;Rodems & Friesen, 1995) ; and two proteins, LEF-1 (a putative primase) and LEF-2, which have been shown to interact with each other . The three gene products, which are stimulatory for DNA replication, include two additional transcriptional activators, IE-2 (Carson et al, 1991) and PE-38 (Krappa & Knebel-Mo$ rsdorf, 1991), and P35, which blocks apoptosis (Clem et al, 1991 ;Herschberger et al, 1992) and may therefore influence DNA replication in an indirect manner.…”