WB- proteins of lower-than-expected MW - (Aug/24/2005 )

Hi All,

I've been trying out westerns for some high molecular weight proteins (Tiam1- 177 kDa, and SRPK-92 kDa) and have been getting lower than expected bands by ECL. Tiam appears around 90kDa and SRPK comes around 60 kDa. I have used the same samples for some other proteins and i get the expected MW bands. My questions are the following:

a. could this be due to consistent degradation in all my samples? I prepared lysates a month ago and kept them stored in aliquots at -80 and -20 and have got these bands in both groups.

b. What other modifications could occur that would result in lower than expected MW bands??

Any suggestions would be highly appreciated...

Thanks for viewing my post...

Molbionovice.

Hi!

Well, I know this is one old topic, but I have now the same problem! My protein (SP1) has around 100kDa and i can`t find it in my WB's. Instead of this, I find a lower band. I made this question one month ago, but nobody could tell me what's happening. Did you find a solution? I though that there was a problem with some denaturing agent: temperature, detergent, ect.

thanks-