strategy of primer designing - difference between designing a primer for expression and cloning.. (Jun/02/2010 )

can anyone give some suggestions about difference between designing a primer for expression and cloning....

or strategy for primer designing of both.....??

For cloning, you need to amplify the whole coding sequence. For expression analysis, you just need to amplify a portion of the mRNA sequence. The size of amplicon depends on the PCR method: for qPCR, the size is usually < 200. for regular PCR, the size can be a few hundreds.