《遗传学》课程教学资源（PPT课件，英文版）Home reading part

Home reading part How DNA as genetic materials was established Basic properties of DNA, including structure and components (also summarized in next slide) DNA Replication DNA transcription RNA translation

Home reading part • How DNA as genetic materials was established • Basic properties of DNA, including structure and components (also summarized in next slide) • DNA Replication • DNA transcription • RNA translation

How DNA recombination is achieved?

How DNA recombination is achieved?

Step l.ecombination: steps 1, 2,3 king DODDOO 43"chromatids followed Iin figure Step 2 Whisker displacement U⑩g RecA subunits DOD Whisker((4 DNA helicase Step 3 First strand invasion First strand invasion DD0Q吗0 Traun D-loop Single-strand binding protien u/u/心QA

Recombination: steps 4, 5, 6 Step 4 Second strand invasion rGap 000g0~A Degradation direction ①~0um风 Second strand invasion Step 5 Repair and ligation Ligation point ~⑩0d Repair and ligation Step 6 Branch migration 00000000dM Direction of migration regions DOMDODADADXD((DM

Gene Conversion: one allele is converted to another C N 2[M Aa mismatch C C NMM wWW a/A mismatch a

Gene Conversion: one allele is converted to another

Mutations are the results of DNA changes Hydrolysis UV and other radiation caused backbone alteration Oxidation

Mutations are the results of DNA changes • Hydrolysis • UV and other radiation caused backbone alteration • Oxidation

(a) Depurination T OH Guanine H Guanine released C C

(b)Deamination Normal Sequence Amino group H G ,UG Deamination N NO H Replication Cytosine Uracil A G Replication A A Mutant sequence

(e)Oxidation Active Normal sequence oxygen H species ↓ Oxidative damage C G canine 8-oxodG Replication GO) Mispairing with A Replication A Mutant sequence

( c)X rays break the DNA backbone X ray Deletion