sentences:  In addition, pY653 and pY654 in the active form helps to maintain the open conformation of the SH2 and FGFR1 kinase complex.However, the mechanism by which the phosphorylation at Y653 and Y654 helps to recruit the SH2 domain to its C-terminal tail upon phosphorylation of Y766 remains elusive.Figure 5 shows the overlay structure of active and inactive forms of FGFR1 kinase.