skip to main content


Search for: All records

Creators/Authors contains: "Weerapana, Eranthie"

Note: When clicking on a Digital Object Identifier (DOI) number, you will be taken to an external site maintained by the publisher. Some full text articles may not yet be available without a charge during the embargo (administrative interval).
What is a DOI Number?

Some links on this page may take you to non-federal websites. Their policies may differ from this site.

  1. Free, publicly-accessible full text available September 20, 2024
  2. Abstract

    The basal complex (BC) is essential forT. gondiicell division but mechanistic details are lacking. Here we report a reciprocal proximity based biotinylation approach to map the BC’s proteome. We interrogate the resulting map for spatiotemporal dynamics and function by disrupting the expression of components. This highlights four architecturally distinct BC subcomplexes, the compositions of which change dynamically in correlation with changes in BC function. We identify BCC0 as a protein undergirding BC formation in five foci that precede the same symmetry seen in the apical annuli and IMC sutures. Notably, daughter budding from BCC0 progresses bidirectionally: the apical cap in apical and the rest of the IMC in basal direction. Furthermore, the essential role of the BC in cell division is contained in BCC4 and MORN1 that form a ‘rubber band’ to sequester the basal end of the assembling daughter cytoskeleton. Finally, we assign BCC1 to the non-essential, final BC constriction step.

     
    more » « less
  3. null (Ed.)
    The reactivity profile of atomic oxygen [O( 3 P)] in the condensed phase has shown a preference for the thiol group of cysteines. In this work, water-soluble O( 3 P)-precursors were synthesized by adding aromatic burdens and water-soluble sulphonic acid groups to the core structure of dibenzothiophene- S -oxide (DBTO) to study O( 3 P) reactivity in cell lysates and live cells. The photodeoxygenation of these compounds was investigated using common intermediates, which revealed that an increase in aromatic burdens to the DBTO core structure decreases the total oxidation yield due to competitive photodeoxygenation mechanisms. These derivatives were then tested in cell lysates and live cells to profile changes in cysteine reactivity using the isoTOP-ABPP chemoproteomics platform. The results from this analysis indicated that O( 3 P) significantly affects cysteine reactivity in the cell. Additionally, O( 3 P) was found to oxidize cysteines within peptide sequences with leucine and serine conserved at the sites surrounding the oxidized cysteine. O( 3 P) was also found to least likely oxidize cysteines among membrane proteins. 
    more » « less
  4. Abstract

    We have developed a novel visible‐light‐catalyzed bioconjugation reaction, PhotoCLIC, that enables chemoselective attachment of diverse aromatic amine reagents onto a site‐specifically installed 5‐hydroxytryptophan residue (5HTP) on full‐length proteins of varied complexity. The reaction uses catalytic amounts of methylene blue and blue/red light‐emitting diodes (455/650 nm) for rapid site‐specific protein bioconjugation. Characterization of the PhotoCLIC product reveals a unique structure formed likely through a singlet oxygen‐dependent modification of 5HTP. PhotoCLIC has a wide substrate scope and its compatibility with strain‐promoted azide‐alkyne click reaction, enables site‐specific dual‐labeling of a target protein.

     
    more » « less
  5. Abstract

    We have developed a novel visible‐light‐catalyzed bioconjugation reaction, PhotoCLIC, that enables chemoselective attachment of diverse aromatic amine reagents onto a site‐specifically installed 5‐hydroxytryptophan residue (5HTP) on full‐length proteins of varied complexity. The reaction uses catalytic amounts of methylene blue and blue/red light‐emitting diodes (455/650 nm) for rapid site‐specific protein bioconjugation. Characterization of the PhotoCLIC product reveals a unique structure formed likely through a singlet oxygen‐dependent modification of 5HTP. PhotoCLIC has a wide substrate scope and its compatibility with strain‐promoted azide‐alkyne click reaction, enables site‐specific dual‐labeling of a target protein.

     
    more » « less