Chapter 24, Problem 24E

(a)

Summary Introduction

To identify: The four-residue segments that are almost identical in the two proteins.

Concept introduction: NS1 protein is a non-essential (nonstructural protein) found in the influenza virus that is encoded by the viruses, yet not a part of the viral particle. They are mainly involved in the inhibitory actions against the host immune responses. H3 protein is one among the five histone proteins. It is a structural variant of the histone protein that is involved in packaging the DNA molecules into a structure called nucleosomes. There are some sequence similarities between the NS1protein of the influenza viruses and the H3 histone proteins.

(b)

Summary Introduction

To explain: How the NS1’s similarity to H3 interferes with the host gene expression.

Concept introduction: NS1 protein is a nonstructural protein found in influenza virus that is encoded by the viruses, yet not a part of the viral particle. They are mainly involved in the inhibitory actions against the host immune responses. H3 protein is one among the five histone proteins. It is a structural variant of the histone protein that is involved in packaging the DNA molecules into a structure called nucleosomes. There are some sequence similarities between the NS1protein of the influenza viruses and the H3 histone proteins.