
@article {73039,
	title = {A Fyn biosensor reveals pulsatile, spatially localized kinase activity and signaling crosstalk in live mammalian cells.},
	journal = {Elife},
	volume = {9},
	year = {2020},
	month = {2020 Feb 04},
	abstract = {<p>Cell behavior is controlled through spatio-temporally localized protein activity. Despite unique and often contradictory roles played by Src-family-kinases (SFKs) in regulating cell physiology, activity patterns of individual SFKs have remained elusive. Here, we report a biosensor for specifically visualizing active conformation of SFK-Fyn in live cells. We deployed combinatorial library screening to isolate a binding-protein (F29) targeting activated Fyn. Nuclear-magnetic-resonance (NMR) analysis provides the structural basis of F29 specificity for Fyn over homologous SFKs. Using F29, we engineered a sensitive, minimally-perturbing fluorescence-resonance-energy-transfer (FRET) biosensor () that reveals cellular Fyn activity to be spatially localized, pulsatile and sensitive to adhesion/integrin signaling. Strikingly, growth factor stimulation further enhanced Fyn activity in pre-activated intracellular zones. However, inhibition of focal-adhesion-kinase activity not only attenuates Fyn activity, but abolishes growth-factor modulation. imaging uncovers spatially organized, sensitized signaling clusters, direct crosstalk between integrin and growth-factor-signaling, and clarifies how compartmentalized Src-kinase activity may drive cell fate.</p>
},
	issn = {2050-084X},
	doi = {10.7554/eLife.50571},
	author = {Mukherjee, Ananya and Singh, Randhir and Udayan, Sreeram and Biswas, Sayan and Reddy, Pothula Purushotham and Manmadhan, Saumya and George, Geen and Kumar, Shilpa and Das, Ranabir and Rao, Balaji M and Gulyani, Akash}
}
@article {79733,
	title = {A novel polyubiquitin chain linkage formed by viral Ubiquitin is resistant to host deubiquitinating enzymes.},
	journal = {Biochem J},
	volume = {477},
	year = {2020},
	month = {2020 Jun 26},
	pages = {2193-2219},
	abstract = {<p>The Baculoviridae family of viruses encode a viral Ubiquitin (vUb) gene. Though the vUb is homologous to the host eukaryotic Ubiquitin (Ub), its preservation in the viral genome indicates unique functions that are not compensated by the host Ub. We report the structural, biophysical, and biochemical properties of the vUb from Autographa californica multiple nucleo-polyhedrosis virus (AcMNPV). The packing of central helix α1 to the beta-sheet β1-β5 is different between vUb and Ub. Consequently, its stability is lower compared with Ub. However, the surface properties, ubiquitination activity, and the interaction with Ubiquitin-binding domains are similar between vUb and Ub. Interestingly, vUb forms atypical polyubiquitin chain linked by lysine at the 54th position (K54), and the deubiquitinating enzymes are ineffective against the K54-linked polyubiquitin chains. We propose that the modification of host/viral proteins with the K54-linked chains is an effective way selected by the virus to protect the vUb signal from host DeUbiquitinases.</p>
},
	issn = {1470-8728},
	doi = {10.1042/BCJ20200289},
	author = {Negi, Hitendra and Reddy, Pothula Purushotham and Vengayil, Vineeth and Patole, Chhaya and Laxman, Sunil and Das, Ranabir}
}
