SASDB44: Aureochrome 1a from P. tricornutum, amino acids 148-378 (N-termin...

Basic information

• Entry: Database: SASBDB / ID: SASDB44

Sample

Aureochrome 1a from P. tricornutum, amino acids 148-378 (N-terminal truncation), dark state

• Aureochrome 1a (N-terminally truncated) (protein), Phaeodactylum tricornutum

• Biological species: Phaeodactylum tricornutum (Diatom)
• Citation: Journal: Elife / Year: 2016; Title: Blue light-induced LOV domain dimerization enhances the affinity of Aureochrome 1a for its target DNA sequence.; Authors: Udo Heintz / Ilme Schlichting / ; Abstract: The design of synthetic optogenetic tools that allow precise spatiotemporal control of biological processes previously inaccessible to optogenetic control has developed rapidly over the last years. Rational design of such tools requires detailed knowledge of allosteric light signaling in natural photoreceptors. To understand allosteric communication between sensor and effector domains, characterization of all relevant signaling states is required. Here, we describe the mechanism of light-dependent DNA binding of the light-oxygen-voltage (LOV) transcription factor Aureochrome 1a from Phaeodactylum tricornutum (PtAu1a) and present crystal structures of a dark state LOV monomer and a fully light-adapted LOV dimer. In combination with hydrogen/deuterium-exchange, solution scattering data and DNA-binding experiments, our studies reveal a light-sensitive interaction between the LOV and basic region leucine zipper DNA-binding domain that together with LOV dimerization results in modulation of the DNA affinity of PtAu1a. We discuss the implications of these results for the design of synthetic LOV-based photosensors with application in optogenetics.

Contact author

• Udo Heintz (Max Planck Institute for Medical Research, Germany)

Models

• Model #481: ; Type: dummy / Software: DAMSTART/DAMMIN / Radius of dummy atoms: 2.50 A / Symmetry: P1 / Chi-square value: 8.567329; Search similar-shape structures of this assembly by Omokage search (details)

Sample

• Sample: Name: Aureochrome 1a from P. tricornutum, amino acids 148-378 (N-terminal truncation), dark state
• Buffer: Name: HEPES / Concentration: 20.00 mM / pH: 7.5 / Composition: 100 mM NaCl, 10 mM MgCl2, 5% w/v glycerol

Entity #313

Type: protein / Description: Aureochrome 1a (N-terminally truncated) / Formula weight: 26.277 / Num. of mol.: 2 / Source: Phaeodactylum tricornutum
Sequence:

GAMGMSEQQK VERRERNREH AKRSRIRKKF LLESLQQSVS LLKEENEKLK TSIRSHLGEE KADTLIDSAN NNKTDVDGLL ASSQGIANKV LDDPDFSFIK ALQTAQQNFV VTDPSLPDNP IVYASQGFLN LTGYSLDQIL GRNCRFLQGP ETDPKAVERI RKAIEQGNDM SVCLLNYRVD GTTFWNQFFI AALRDAGGNV TNFVGVQCKV SDQYAATVTK QQEEEEEAAA NDDED

Experimental information

• Beam: Instrument name: Swiss Light Source cSAXS / City: Villigen / 国: Switzerland / Type of source: X-ray synchrotron / Wavelength: 0.1 Å / Dist. spec. to detc.: 2.15 mm
• Detector: Name: Pilatus 2M

Scan

Title: N-terminally truncated Aureochrome 1a / Measurement date: Mar 11, 2015 / Storage temperature: 10 °C / Cell temperature: 10 °C / Exposure time: 0.5 sec. / Number of frames: 10 / Unit: 1/nm /

	Min	Max
Q	0.1419	3.2007

Distance distribution function P(R)

Sofotware P(R): GNOM 4.5a / Number of points: 282 /

	Min	Max
Q	0.01671	0.2735
P(R) point	5	286
R	0	97.9

Result

Type of curve: single_conc

	Experimental	Porod	Estimated	Estimated method
MW	54.225 kDa	56.403 kDa	-	-
Volume	-	90.25 nm3	108.5	DAMMIN ab initio model

	P(R)	P(R) error	Guinier	Guinier error
Forward scattering, I0	57.17	0.03	58.02	0.06
Radius of gyration, Rg	2.804 nm	0.002	2.88 nm	0.01

	Min	Max
D	-	9.79
Guinier point	1	60