Genome size (Lucy)

Question 1

Why does genome size matter?

Answer 1

It determines how much sequencing you need to do to get a complete genome seq

Question 2

How much does it cost to seq a human genome?

Answer 2

Costs around £100 to seq single nucleotide variants (3x10^9 bp)

(More if we want telomere to telomere (T2T) contiguity & structureal variants)

Question 3

How big is a typical protein?

Answer 3

About 333 amino acids in length

(So requires ~1kb (1000bp) of coding info)

Question 4

Are genomes of complex multicellular organisms larger than those of simple unicellular organisms?

Answer 4

NO

Question 5

What is the genome size and gene number for E.coli?

Answer 5

Genome size = 4.5Mb

Gene number = 4,300

Question 6

What is the genome size and gene number for S.cerevisiae?

Answer 6

Genome size = 15Mb

Gene number = 5,700

Question 7

What is the genome size and gene number for C.elegans?

Answer 7

Genome size = 100Mb

Gene number = 18,400

Question 8

What is the genome size and gene number for D.melanogaster?

Answer 8

Genome size = 180Mb

Gene number = 13,600

Question 9

What is the genome size and gene number for A.thaliana?

Answer 9

Genome size = 120Mb

Gene number = 15,000

Question 10

What is the genome size and gene number for Humans?

Answer 10

Genome size = 3000Mb

Gene number = 19,000-20,500

Question 11

What is the genome size and gene number for Zea Mays?

Answer 11

Genome size = 4,500Mb

Gene number = 15,000

Question 12

What is the genome size and gene number for Amphiuma?

Answer 12

Genome size = 76,500Mb

Gene number = ~20,000

Question 13

How many bp is in 1Mb?

Answer 13

1MB = 1000kb = 1,000,000bp

Question 14

Give an example of a genome that is bigger than ours:

Answer 14

Lillies have a genome 30x bigger than ours (90,000, not one of the key numbers to remember)

Question 15

How do our genes compare to e.coli?

Answer 15

We only have 4x as many genes as e.coli

Question 16

What is the “C value paradox”?

Answer 16

C value paradox often stated as “no relationship between organismal complexity and genome size”

NOT always true

Question 17

Give an example of the C value paradox being true:

Answer 17

Genome is 40X bigger in Protopterus aethiopicus (type of fish) than humans –> fish not more complicated

Question 18

According to the C value paradox does genome size scale with the complexity of the organism?

Answer 18

Yes, when many organisms were compared there was an approx relationship - but there are outliers, these pose the C value paradox*

Data was plotted & showed a linear relationship (Megan if you could insert the graph would be fab xx)

*(The breakdown in the non linear relationship = the C value paradox)

Question 19

What are the outliers in the C value paradox? (Linear relationship between genome size & complexity of organisms)

Answer 19

Lillies and lung fish (are the most comonly used examples of outliers)

Question 20

What size can a bacterial genome range from?

Answer 20

Range in size from ~0.5Mb to 10Mb

(They DO NOT show any evidence for C value paradox)

Vary over 20 fold range: Mycoplasma genitalium 580kb - Sorangium cellulosum 13,000kb

Question 21

What size is a small genome in a bacteria & what is its role generally?

Answer 21

Small genome (470 genes)

They are specialists, usually obligate parasites

Question 21

What are the general structure of bacterial genomes

Answer 21

Bacterial genomes are mainly circular - soem are linear such as; Streptomyces coelicolor, Agrobacterium tumefaciens, Borrelia burgdorferi

Question 22

What size is a large genome in bacteria & what is its role generally?

Answer 22

Large genome (~10,000 genes)

Metabolic generalists often undergoing some form of development

Question 23

Are eukaryotic genomes always bigger than prokaryotic?

Answer 23

NO!!

Eukaryotic genomes are not always bigger than prokaryotic genomes

Question 23

Finish from crpyomonad nucleomorph

Answer 23

Need to watch the video on this bc missing notes

Question 23

What is special about Candidatus thiomargarita?

Answer 23

It is a type of bacteria that is very large (Ca. Thiomargarita magnifica) can be over 1cm in size

(Margarita = pearl in italian, these bacteria have a pearl like apperance)