How old is the ancestral protein likely to be

[ho&ho]

hi, anyone could shed some light on this puzzle pls,

how to estimate when in evolution did a ncestral protein arise, in other words, How old is the ancestral protein likely to be? detail as bellow,

 

there is a amino-acid sequence of part of the AntP gene product , KRGRQTYTRYQTLELEKEFHFNRYLTRRRRIEIAHAL

 

Use this to do a BLAST search to find other proteins related to Drosophila AntP. First open the BLAST page at NCBI. Choose the Standard Protein Blast option (BlastP), and copy and paste the sequence into the search box. Click "Blast!" to do the search, then click the Format button to see the results. This will give a long list of proteins that match the sequence, either approximately or exactly. How old is the ancestral protein likely to be.

 

i v got the long list of protiens and the distance tree, however , i can tell how old it is . thanks

[Bluenoise]

The problem is that different proteins evolve at different rates. So to determine how long ago two proteins diverged from each other you need to know how quickly these two diverge from each other. Once you know that there is a relationship between evolutionary distance and time.

 

To determine the rate one usually needs an inital time frame or another rate for comparison.