Difference between Histone and Non-Histone Proteins

Histone and non-histone proteins are components of chromatin that help in the structuring, scaffolding and packaging of DNA into chromosomes. Chromatin is the condensed form of DNA in a chromosome. The histone and non-histone proteins together pack the chromatin together into chromosomes. Let us look at the differences between the two proteins.

Histone Proteins
Non-Histone Proteins
Definition
Histone proteins are the chief protein components of chromatin. Non-histone proteins are the proteins left after all the histone proteins have been removed from chromatin.
Types
There are five major types of histone proteins: H1/H5, H2A, H2B, H3, and H4. They include scaffold proteins, DNA polymerases, heterochromatin protein 1, and polycomb. They also include several other structural, motor and regulatory proteins.
Functions
It acts as a spool around which the DNA can bind to form structures called nucleosomes. They help in the organisation and compaction of chromosomes into higher-order structures.
They play a major role in protecting the DNA from tangling and damage. Not involved in the protection of DNA.
Other functions include gene regulation and DNA replication. Other functions include nucleosome remodelling, nuclear transport and interphase transition.
Nature of the protein
They are highly basic in nature, making them highly soluble in water. They are acidic in nature.
Conservation
The histone proteins are conserved across the species. Non-histone proteins are not conserved across the species.

Also Read:

Visit BYJU’S Biology for more interesting topics.

Frequently Asked Questions

Q1

What is the function of non-histone proteins?

Non-histone proteins are associated with the scaffolding of DNA structures. They play an important role in regulating processes such as replication, transcription, nucleosome remodelling, etc.

Q2

What is the main difference between a histone and a nucleosome?

Histone proteins are the proteins that help in the packaging of DNA structures, whereas nucleosomes are the basic structural unit of DNA packaging that are formed after DNA is wrapped around the core of histone proteins (histone octamer).

Q3

What are histone proteins, and what is their role?

Histone proteins are the basic proteins of chromatin that help in the packaging and in giving structure to the chromosomes.

Q4

What is the nature of non-histone proteins?

Non-histone proteins are acidic in nature.

Q5

How many types of non-histone proteins are there?

Non-histone proteins include a variety of proteins like structural proteins, motor proteins and regulatory proteins.

Q6

Do prokaryotes have histone proteins?

With the exception of the Archea group, most prokaryotes do not have histone proteins. They wrap their DNA by supercoiling.

Comments

Leave a Comment

Your Mobile number and Email id will not be published.

*

*