tokens: Although the Src tyrosine kinase induces constitutive Stat3 phosphorylation on tyrosine , activation of Stat3 mediated gene regulation requires both tyrosine and serine phosphorylation of Stat3 .
folded_tokens: although the src tyrosine kinase induce constitutive stat3 phosphorylation on tyrosine , activation of stat3 mediate gene regulation require both tyrosine and serine phosphorylation of stat3 .