Final Answer:
The protein used to prime PhiX174 and E. coli lagging strand is _RNA primase_.
Step-by-step explanation:
In DNA replication, the lagging strand synthesis involves the creation of short RNA primers to initiate the synthesis of Okazaki fragments.
The enzyme responsible for synthesizing these RNA primers is RNA primase. This primase synthesizes short RNA sequences, typically around 10 nucleotides in length, complementary to the DNA template. These RNA primers provide the necessary 3'-OH group for DNA polymerase to initiate the synthesis of the lagging strand during DNA replication.
PhiX174 is a bacteriophage with a single-stranded DNA genome. In the case of PhiX174 and E. coli, RNA primase plays a critical role in initiating the synthesis of the lagging strand during DNA replication. The RNA primers are later removed and replaced with DNA nucleotides by DNA polymerase, resulting in the completion of the lagging strand.
Understanding the functions of enzymes like RNA primase in DNA replication is essential for unraveling the intricacies of genetic processes and the molecular mechanisms that underlie the faithful duplication of genetic material in living organisms.