Final answer:
A few nonhistone proteins part of the chromatin structure are DNA polymerase, RNA polymerase, and ligase, which are involved in DNA replication and repair. Transcription factors, topoisomerases, and helicase participate in gene expression and DNA structure maintenance. Primase, SSBs, and DNA topoisomerase-II are also critical to the process of DNA replication. The correct option is A.
Step-by-step explanation:
Among the nonhistone proteins that are part of the chromatin structure, several play key roles in DNA replication, repair, and gene expression. We would expect to find proteins like DNA polymerase, RNA polymerase, and ligase in the chromatin because they are directly involved in essential processes such as DNA replication and maintenance.
DNA polymerase is crucial for adding new nucleotides during replication, while RNA polymerase plays a critical role in transcribing genes into RNA. DNA ligase is important for sealing breaks in the DNA strand, ensuring the integrity of the genetic material.
Other nonhistone proteins such as transcription factors, topoisomerases, and helicase also associate with chromatin. These proteins are crucial for gene expression and DNA structure modification.
Transcription factors are necessary for the initiation and regulation of transcription, while topoisomerases help in managing DNA supercoiling during replication and transcription, which is essential for the untangling of the DNA helix. Helicase unwinds the DNA double helix to enable replication and transcription processes.
From the chromatin context, nonhistone proteins like primase, single-strand binding proteins (SSBs), and DNA topoisomerase-II are also involved in the DNA replication and modification processes.
Primase synthesizes RNA primers required for DNA polymerase to start replication. SSBs stabilize the unwound DNA, and DNA topoisomerase-II, specifically gyrase in prokaryotes, alters the topology of DNA.