AP Bio - QUEST 35-37

mutations, gene specialization, regulation

operon's default state is expressing (inducible/repressible)

repressible

operon's default state is off (inducible/repressible)

inducible

How is glucose related to the LAC operon?

Prokaryotes prefer to consume Glucose over Lactose, meaning that if glucose is available, it will indirectly inhibit lactose.

RNA polymerase is by default not able to bind, requiring an activator protein. (positive/negative regulation)

positive

RNA polymerase is by default able to bind, but can be blocked by a repressor protein. (positive/negative regulation)

negative

Transcriptional Regulation (eukaryotes)

A group of transcription factors bind to the promoter (as positive regulatory molecules).

RNA Processing Regulation

Addition of: (for recognition)

• GTP Cap to the 5’ end

• Poly(A) tail to the 3’ end

• Splicing of introns and exons (introns are removed, exons are kept)

• RNA editing (sequence)

RNA Stability/Translation Regulation:

• siRNA (small interfering RNA)

• miRNA (micro RNA)

Degrades or inhibits translation.

Post-Translational Modification

• Addition of phosphate groups (active/inactive switch)

• Addition of methyl/acetyl groups (open/close DNA)

• Addition of sugar molecules to AA side chains (folding and stability)

Totipotent

Can become any type of cell (able to duplicate to an entire organism)

Pluripotent

Can become any type of cell, somewhat more limited

Multipotent

Can form a limited number of types of cells

Pax6

allows for the creation of an eye in an organism.

master regulator

(master regulator, switch for many genes + an entire developmental pathway)

Evolutionary Conservation

 Transcription factor was present in the last common ancestor of many species, and maintained through evolution.

Point Mutation

Change in a single nucleotide

Nonmutant

Point: original strand, no changes

Silent

point, The original amino acid is still produced with a different combination.

Missense

point, A different protein is translated.

Small Insertions / Deletions

Deletion / insertion of a small sequence of nucleotides.

Mutant

i/d, results in a new/missing protein

Frameshift

i/d, reading frame is shifted

Transposons

“jumping genes” - can move from one place to another in a genome.

Non-coding RNA

inhibits

Positive Gene Regulation

: A regulatory protein binds to the operator region, allowing transcription.

Negative Gene Regulation:

A regulatory protein is removed from the operator region, allowing transcription.

Enhancer region:

50-100 codons downstream, something is more likely to be activated.