1. Large-Scale Expansions of Friedreich's Ataxia GAA Repeats in Yeast
Alexander A. Shishkin, Irina Voineagu, Robert Matera, Nicole Cherng, Brook T. Chernet, Maria M. Krasilnikova, Vidhya Narayanan, Kirill S. Lobachev, Sergei M. Mirkin 
Molecular Cell 
Volume 35, Issue 1, Pages (July 2009)
DOI: /j.molcel
Copyright © 2009 Elsevier Inc. Terms and Conditions

2. Figure 1
Selectable System to Detect Large-Scale GAA Repeat Expansions in Yeast
(A) Selectable cassettes for repeat expansions in two orientations in chromosome III. (Gray area) Split URA3 gene. (Hatched area) ACT1 intron. (White rectangle) GAA repeat. (Arrows) PCR primers.
(B) Characteristic results of the PCR analysis of 5-FOAR clones originated from a cassette with 100 GAA repeats, showing expansions, mutations, and deletions. Black arrow designates electrophoretic mobility of the PCR product from the original (GAA)100 repeat.
(C) Schematic representation of mutations and small-scale deletions in 5-FOAR clones. (Stars) Point mutations. (Triangle) A microinsertion. (Gapped lines) Small deletions, with sequence microhomologies shown in parentheses.
(D) Mapping of large deletions using Southern blot hybridization.
Molecular Cell  , 82-92DOI: ( /j.molcel )
Copyright © 2009 Elsevier Inc. Terms and Conditions

3. Figure 2 Rates and Length Distributions of Expanded Repeats
(A) Rates and 95% confidence intervals of expansions, mutations, and deletions for the GAA repeats of varying lengths.
(B) Dependence of expansion rates on repeat lengths. (Red diamonds) Expansions. (Blue circles) Mutations. (Green triangles) Large deletions.
(C) Length distributions of expanded repeats among 5-FOAR clones. (Black bars) Expansions of the (GAA)100 repeat. (Orange bars) Expansions of the (GAA)150 repeat.
Molecular Cell  , 82-92DOI: ( /j.molcel )
Copyright © 2009 Elsevier Inc. Terms and Conditions

4. Figure 3
Expansion Rates and Length Distributions of Expanded Repeats Depend on Balancing the Intron's Length
(A) Repeat expansion rates in length-balanced or unbalanced introns.
(B) Length distributions of expanded repeats among 5-FOAR clones. (Black bars) Expansions of the (GAA)100 repeat in the original intron. (Gray bars) Expansions of the (GAA)100 repeat in the length-balanced intron.
Molecular Cell  , 82-92DOI: ( /j.molcel )
Copyright © 2009 Elsevier Inc. Terms and Conditions

5. Figure 4
Effects of Expanded GAA Repeats on the Expression of the Intronated URA3 Gene
(A) Diagram showing primers used for the RT-PCR experiments. (Black arrows) For mRNA. (Gray arrows) For unspliced RNA.
(B) Characteristic results of the RT-PCR analysis of the spliced and unspliced URA3 RNA, as well as ACT1 mRNA used as normalization control. RT− is a negative control without reverse transcriptase to rule out DNA contamination.
(C) Quantitative analysis of the data in (B). (Black bars) Normalized spliced RNA. (Hatched bars) Normalized unspliced RNA. Error bars indicate SD of three independent experiments.
Molecular Cell  , 82-92DOI: ( /j.molcel )
Copyright © 2009 Elsevier Inc. Terms and Conditions

6. Figure 5 Replication Stalling and Expansions of GAA Repeats
(A) Replication fork progression through the GAA100 repeat in chromosome III. Repeat orientations correspond to that in Figure 1A.
(B) Rates of expansion for GAA repeats in various orientations within the replicon. Error bars indicate SD of three independent experiments.
Molecular Cell  , 82-92DOI: ( /j.molcel )
Copyright © 2009 Elsevier Inc. Terms and Conditions

7. Figure 6 Proposed Mechanisms of Expansions of the GAA Repeats
(A–D) The homopurine strand of the repeat is shown in red, and homopyrimidine strand is in green. (Blue hexameric ring) The Mcm2–7 replicative DNA helicase. (Purple star) Fork-pausing complex Tof1/Csm3/Mrc1. (Yellow circles) Leading and lagging DNA polymerases. (Gray square) Rad5 and, possibly, Sgs1 implicated in DNA template switching.
Molecular Cell  , 82-92DOI: ( /j.molcel )
Copyright © 2009 Elsevier Inc. Terms and Conditions