We then performed an RNA binding experiment in which SNF was mixed with different RNA fragments (RNA A, B, C and D) of the Sxl transcript (Figure 2A).
We note that in those SEC binding experiments in vitro in which we used isolated BubR1 rather than BubR1/Bub3, Bub3 might have exchanged from the Bub1/Bub3 complex to reconstitute BubR1/Bub3.
Assay to assay (inter-assay) variability was assessed with normalized Ct values from three independent experiments, in which antibody binding, SH2 binding, ligation, protease treatment, and real-time PCR reactions were independently performed while using the same batch of cell lysate samples.
The qualitative version of the fluorescence assay employed DNGSH in competition experiments, in which binding of a ligand results in displacement of DNGSH and a consequent decrease in fluorescence intensity.
Additional confirmation of binding specificity was obtained from competition experiments in which the wild-type, but not a mutated, SL3 oligonucleotide effectively competed with probe for L22 binding (compare 100× SL3 with 100× mSL3, Fig. 3B).
First, allelic series experiments in which adaptor binding is abrogated in order to abolish specific effector cascades may result in induction of alternate signaling pathways, complicating assignment of developmental function to a single intracellular pathway.
Experiments in which the binding of PII to the ATase was directly examined by gel-filtration chromatography or nondenaturing gel electrophoresis indicated that under certain conditions, glutamine was required to detect the complex of PII and ATase (10).
As an early study indicates that the normal function of AP2 in EGFR endocytosis may be bypassed by experimental manipulation of incubating cells with EGF first at 4°C followed by endocytosis at 37°C (Huang et al, 2004), we have also performed experiments in which both binding and endocytosis were carried out at 37°C.
Support for this model comes from experiments in which Cdc13 binding at a DSB flanked by either 80 or 250 bp of TG repeat sequence was measured by a quantitative ChIP assay and found to be considerably reduced at the longer end (Negrini et al, 2007).
All measurements of binding were corrected using control dilution ITC experiments in which the nucleotide or MP265 was injected into appropriate buffer alone.
