Question

Correctly identify the processes, steps, and molecules produced in the time course of a typical T4 phage infection of a bacterial host cell. Drag the appropriate labels to their respective targets. Reset Help Phage head proteins T4 lysozyme production Lysis Infection Tail, collar, base plate, and tail fiber proteins T4 nucleases, DNA polymerase, and new sigma factors → 21 Phage T4 DNA Mature T4 virion Phage DNA replication Transcription Early mRNA Middle mRNA Translation Early proteins Middle proteins Late mRNA Self-assembly Late proteins 10 15 20 Minutes

Answer 1

The figure shows the time course of events in T4 infection and gene expression.

The DNA of T4 has an unusual base (5-hydroxymethyl cytosine) and the enzymes that are required to synthesize are only formed by infection of the phage.T4 genes are divided into three groups; early, middle and late genes. T4 does not have its own RNA polymerase, thus, its mRNA synthesis is controlled by host RNA polymerase, thus modify the specificity of the host RNA polymerase. T4 viruses some gene expression to the later stages of infection, early genes are transcribed after 5 minutes of infection, middle after 10 minutes and finally transcription of late genes begins. Early proteins include nuclease that breaks host DNA, middle includes primases, helicase, endonuclease, and ligase while late proteins include capsid proteins, head, tail, collar plate, tail fiber proteins, lysozyme, etc.

Correctly identify the processes, steps, and molecules produced in the time course of a typical T4 phage infection of a bacterial host cell. Drag the appropriate labels to their respective targets. Reset Help Phage head proteins T4 lysozyme production Lysis Infection Tail, collar, base plate, and tail fiber proteins T4 nucleases, DNA polymerase, and new sigma factors T4 nucleases, DNA polymerase, and new sigma factors Phage T4 DNA phage head proteins Mature T4 virion Tail, collar, base plate & tail fiber proteins T4 lysozyme production infection Phage DNA replication Transcription Early mRNA Middle mRNA Translation Early proteins Middle proteins Late mRNA Self-assembly Late proteins lysis 10 15 20 25 Minutes