Dr May's BS2009 Puzzle No.1

2. Branched nucleic acid structure containing four double-stranded arms joined together.(8,8)
3. Huntington's disease is a consequence of what within the HTT gene?(13,9)
6. How many leading strands would you find at a single replication origin?(3)
15. A cis-acting element that defines the start of replication in simple eukaryotes.(10,11,8)
16. A key effector in the DNA damage response.(3)
17. Type of slippage that leads to contraction of tandemly repeated sequences.(7)
18. Protein that relieves structural stress during replication.(13)
20. Key sensor involved in error-prone repair of double-strand breaks. (2, 11)
22. What term is used to define "inefficient replication that leads to fork slowing, stalling and or breakage?(3,11,6)
23. Microsatellite instability is a hallmark of an impaired repair pathway. Which one? (8,6)
24. Nuclear division.(7)
25. Error-prone pathway that makes use of sequence similarity to repair a double-strand break. (6,6,9)
26. Normal activity of the replication-associated protein that can lead to Werner's syndrome. (8)

1. Pathway used to repair a pyrimidine dimer.(10,8,6)
4. The two strands of DNA are said to be.... (4-8)
5. Cell division. (11)
7. What is the major reason for replication termination in eukaryotes? (5,8)
8. Loss of heterozygosity can occur when what is used to repair a double-strand break? (3-6,9)
9. The base pairing within DNA is said to be ........ (13)
10. Cell cycle phase that includes G1,S and G2. (10)
11. Name of editing activity of DNA polymerase.(11)
12. Permanent cell cycle arrest. (10)
13. Temporary arrest in cell cycle.(10)
14. What happens in all homology-directed repair once a double strand break forms?(9)
19. DNA replication is said to be what type of process? (4-12)
21. Enzyme activity responsible for formation of Okazaki fragments.(3,7)