DNA RNA Protein

Genes, DNA->RNA->protein

DNA {A,T,C,G}

5' [up stream]

[promoter(s)]

[exon1]

[gt intron1 ag]

[exon2]

[gt intron2 ag]

[exon3]

3' [down stream]

transcribed to RNA {A,U,C,G}

[exon1]

[gu intron1 ag]

[exon2]

[gu intron2 ag]

[exon3]

RNA spliced (edited)

[ exon1 ]		[exon2]	[ exon3 ]
[UTS	aug... ]	[exon2]	[ ...	UTS]

translated to protein

protein

	R purine	Y pyrimidine
	N any
small 2xH	A	U/T
large 3xH	G	C

atg~aug->MET (& starts)

Stop translation codons:
taa~uaa, tag~uag, tga~uga

UTS = UnTranslated Sequence

Genetic Code

There are four DNA (RNA) bases {A,T(U),C,G}. There are twenty (common) amino acids making up proteins. mRNA is read in codons - groups of three bases - and translated into protein according to the genetic code below:

			pyrimidine				purine
			position 2
			U/T		C		A		G
p o s i t i o n 1	p y r i m i d i n e	U / T	UUU	Phe[F]	UCU	Ser[S]	UAU	Tyr[Y]	UGU	Cys[C]	U	p o s i t i o n 3
			UUC	Phe[F]	UCC		UAC	Tyr[Y]	UGC	Cys[C]	C
			UUA	Leu[L]	UCA		UAA	Stop!	UGA	Stop!	A
			UUG		UCG		UAG	Stop!	UGG	Trp[W]	G
		C	CUU		CCU	Pro[P]	CAU	His[H]	CGU	Arg[R]	U
			CUC		CCC		CAC	His[H]	CGC		C
			CUA		CCA		CAA	Gln[Q]	CGA		A
			CUG		CCG		CAG	Gln[Q]	CGG		G
	p u r i n e	A	AUU	Ile[I]	ACU	Thr[T]	AAU	Asn[N]	AGU	Ser[S]	U
			AUC		ACC		AAC	Asn[N]	AGC	Ser[S]	C
			AUA		ACA		AAA	Lys[K]	AGA	Arg[R]	A
			AUG	Met[M]	ACG		AAG	Lys[K]	AGG	Arg[R]	G
		G	GUU	Val[V]	GCU	Ala[A]	GAU	Asp[D]	GGU	Gly[G]	U
			GUC		GCC		GAC	Asp[D]	GGC		C
			GUA		GCA		GAA	Glu[E]	GGA		A
			GUG		GCG		GAG	Glu[E]	GGG		G

--->
A	Ala
C	Cys
D	Asp
E	Glu
F	Phe
G	Gly
H	His
I	Ile
K	Lys
L	Leu
M	Met
N	Asn
P	Pro
Q	Gln
R	Arg
S	Ser
T	Thr
V	Val
W	Trp
Y	Tyr

--->
Ala	A
Arg	R
Asn	N
Asp	D
Cys	C
Gln	Q
Glu	E
Gly	G
His	H
Ile	I
Leu	L
Lys	K
Met	M
Phe	F
Pro	P
Ser	S
Thr	T
Trp	W
Tyr	Y
Val	V

codes

There are three stop (translating) codons. All coding regions begin AUG (Met).

Any "sufficiently long" stretch of DNA, in some reading frame (offset of 0, 1 or 2), not containing a stop codon is called an open reading frame (ORF) and is a potential candidate for being a part of a gene.

AA Properties

--Approx(!) AA similarity ~ Swanson 84--
.	--hydrophylic--							.
l a r g e	.	.	K	Q	E D	.	.		s m a l l
	.	H	R	N	.	.	.
	.	.	.	.	.	P	G
	W	.	.	*	T	S A	.
	.	.	M	.	.	.	.
	.	F L	.	I V	.	.	.
	.	Y	.	.	.	.	C
.	--hydrophobic--							.