BIOL 3090 : BIOL 3090 Exam 3
Document Summary
14-100 bp: usually occur in tandem repeats of 150 repeats or fewer, 1-5 kb regions with 20-50 repeat units per region. Copia particles containing rna accumulate in the nuclei and are expressed during stress: contain long terminal repeats (ltrs). Ltr retrotransposons constitute ~8% of human genomic dna: they encode 3-4 proteins. It also exhibits dna endonuclease activity: only members of the l1 family tranpose in the contemporary human, l1 insertions cause mutations. This is how they were first discovered genome: transposes by an rna intermediate making it retro , most l1s are defective and cannot transpose by themselves, only need one functional l1 element to provide proteins, mechanism, step 1: Poly(a) tail: steps 3-5, orf2 reverse transcribes the line. Dna strand, switching to the single stranded region of the upper chromosomal strand as a template: transposase holds everything together, step 6, cellular enzymes then hydrolyze the.
