Forward genetics in Arabidopsis thaliana.

What is the most common way to induce random mutations in Arabidopsis thaliana forward genetic approaches?

• Exposure to gamma-rays

• Treatment of seeds with ethyl methanesulfonate (EMS)

• Mutagenesis with the use of CRISPR-Cas9 method

• Treatment of mature plants with ethyl methanesulfonate (EMS)

How does EMS induce mutations in plants?

• EMS causes DNA breaks which are incorrectly repaired

• EMS binds to DNA polymerase reducing its specificity

• EMS alkylates guanine residues changing their pairing specificity

• EMS does not induce mutations in plants

EMS-induced mutations are always recessive

• True

• False

Phenotypes caused by recessive mutations segregate 7:1 in the progeny of M2 plants. How about dominant mutations?

• WT : mutant

  0 : 4

• WT : mutant

  7 : 1

• WT : mutant

  3 : 1

• WT : mutant

  5 : 3

Easy-to-score phenotype is a prerequisite for a successful forward genetic screen

• Yes

• No

In plants, genetic mapping usually does not involve:

• Crossing

• Phenotyping of mapping population

• DNA isolation

• RNA isolation

When looking at mapping results we should not focus on:

• Genes that we personally find the most interesting

• Non-synonymous mutations

• High-frequency mutations

• Mutations within exon/intron junctions