Transposable elements

Question 1

What did Petrov (2011) find in D. melanogaster?

Answer 1

In over 70 strains there were 755 TEs. These never occurred in exons, implying strong selection. All found in introns. This is because TEs are very rare in high areas of recombination.

Question 2

What is a P element and who described it?

Answer 2

Khurana et al. (2011)
A TE that has invaded D. melanogaster populations. The female cytoplasm suppresses the P element, so F1 with a female P element are fertile. F1 with a P element father are not fertile, no repression.

Question 3

What else did Khurana et al. (2011) describe?

Answer 3

The Piwi system in flies.
piRNA is anti-sense TE, binds TEs, piwi and aubergine bind piRNA, flagging them for destruction by argonaute protein. Mechanism for host repression.

Question 4

Who described the self-repression mechanisms of the IS10 TE in E. coli? What are the mechanisms?

Answer 4

Kleckner (1990)

1. Methylation (removal increases transmission by 100x)
2. Anti-sense RNA inhibitor that binds transcriptase

Question 5

What did Gifford et al. (2013) describe?

Answer 5

The env protein from a retroTE in several mammalian lineages mediates cell-cell fusion in the placenta

Question 6

The maize genome doubled over 3mya due to LTRs. Who described this?

Answer 6

San Miguel et al. (1998)