At Its Core
These positively charged proteins help neutralize the negative charge of DNA, enabling it to wrap tightly into nucleosomes.
What are histones?
This type of RNA makes up 98% of the transcriptional output of the human genome and does not code for proteins.
What are noncoding RNAs?
This domain of transcription factors directly contacts DNA, allowing proteins to activate or inhibit transcription.
What is the DNA‑binding domain?
This type of RNA modification includes trimming leader and trailer sequences, adding terminal sequences, and modifying specific bases.
What is posttranscriptional RNA processing?
These DNA sequences are expressed in the final mRNA and remain after introns are removed.
What are exons?
Acetylation of lysine residues on histone tails reduces this type of interaction, loosening chromatin structure
What is electrostatic interaction between histones and DNA? or What is ionic interactions between the histones and DNA
These short RNAs regulate gene expression and are especially important in growth and development.
What are microRNAs (miRNAs)?
This common structural motif consists of an α‑helix that fits into the major groove of DNA, allowing sequence‑specific binding
What is the helix–turn–helix (HTH) motif?
These RNAs undergo modifications such as methylation and sulfur substitution after being transcribed as one long precursor molecule.
What are transfer RNAs (tRNAs)?
This RNA processing step requires cleavage at both ends of an intron and joining the two coding regions while forming a lariat intermediate.
What is RNA splicing?
This histone tail modification is strongly associated with heterochromatin formation and gene silencing, especially at H3K9.
What is histone methylation?
This type of small RNA selectively suppresses gene expression, often by degrading mRNA.
What is siRNA (small interfering RNA)?
These repeating structures—each containing two cysteines and two histidines—bind Zn²⁺ ions and allow proteins to interact with DNA.
What are zinc fingers?
This eukaryotic mRNA feature consists of a guanylate residue methylated at the N‑7 position and linked to the RNA by a 5′–5′ triphosphate bond.
What is the 5′ cap?
These small complexes mediate the recognition of splice sites in the nucleus.
What are snRNPs?
This family of enzymes adds acetyl groups to lysine residues on histone tails, generally promoting transcription.
What are histone acetyltransferases (HATs)?
This protein complex is guided by miRNAs or siRNAs to silence gene expression.
What is the RISC complex (RNA-induced silencing complex)?
This transcription factor for RNA polymerase III was found to contain nine zinc‑finger repeats, each coordinated by a zinc ion.
What is TFIIIA?
These noncoding sequences must be removed during mRNA processing because they do not appear in the final mRNA.
What are introns?
About 5% of human proteins exist in different structural forms due to this process occurring during mRNA maturation.
What is alternative RNA splicing? or What are isoforms?
This family of ATP‑dependent remodelers alters nucleosome conformation at promoters to regulate transcription and is characterized by chromodomains that help target them to specific histone marks.
What are CHD remodelers? or what are Chromatin remodeling complexes.
Noncoding RNAs are involved in this wide‑ranging set of cellular activities, which includes gene silencing, replication, RNA processing, translation, protein stabilization, and protein translocation.
What are regulatory cellular processes?
This protein motif includes a basic region rich in lysine, arginine, and histidine, paired with a leucine‑repeat region that forms a hydrophobic interface.
What is the basic‑region leucine zipper (bZIP) motif?
This 100–200 nucleotide tail is added to the 3′ end of eukaryotic mRNA to protect it from nucleases.
What is the poly(A) tail?
These proteins influence the recognition of splice sites, enabling a single gene to produce different mRNA isoforms.
What are regulatory splicing proteins?