Toolkit/AzoSM

AzoSM

RNA Element·Research·Since 2021

Also known as: photoswitchable SM

Taxonomy: Mechanism Branch / Component. Workflows sit above the mechanism and technique branches rather than replacing them.

Summary

Using a photoswitchable SM (AzoSM), we observed that the raft-promoting conformation (trans-AzoSM) resulted in efficient phagocytosis, whereas the raft-inhibiting conformation (cis-AzoSM) significantly but reversibly blunted phagocytosis.

Usefulness & Problems

Why this is useful

AzoSM is a photoswitchable sphingomyelin used to shift membranes between raft-promoting and raft-inhibiting states. In this paper, trans-AzoSM supported efficient phagocytosis while cis-AzoSM blunted it reversibly.; reversible perturbation of sphingomyelin-dependent membrane raft state; testing how membrane order affects IgG-mediated phagocytosis

Source:

AzoSM is a photoswitchable sphingomyelin used to shift membranes between raft-promoting and raft-inhibiting states. In this paper, trans-AzoSM supported efficient phagocytosis while cis-AzoSM blunted it reversibly.

Source:

reversible perturbation of sphingomyelin-dependent membrane raft state

Source:

testing how membrane order affects IgG-mediated phagocytosis

Problem solved

It provides a way to test whether sphingomyelin-dependent membrane order directly affects FcγR-linked phagocytosis.; enables switchable control of sphingomyelin conformation to probe raft-dependent phagocytosis

Source:

It provides a way to test whether sphingomyelin-dependent membrane order directly affects FcγR-linked phagocytosis.

Source:

enables switchable control of sphingomyelin conformation to probe raft-dependent phagocytosis

Problem links

enables switchable control of sphingomyelin conformation to probe raft-dependent phagocytosis

Literature

It provides a way to test whether sphingomyelin-dependent membrane order directly affects FcγR-linked phagocytosis.

Source:

It provides a way to test whether sphingomyelin-dependent membrane order directly affects FcγR-linked phagocytosis.

Published Workflows

Cholesterol and sphingomyelin are critical for Fcγ receptor–mediated phagocytosis of Cryptococcus neoformans by macrophages

2021

Objective: Evaluate whether ordered plasma membrane domains enriched in cholesterol and sphingomyelin govern macrophage phagocytosis of Cryptococcus neoformans and associated FcγR signaling.

Why it works: The workflow perturbs membrane order using depletion, sterol replacement, and a photoswitchable sphingomyelin, then tests whether phagocytosis and FcRγ phosphorylation change in parallel. Convergent effects across these perturbations are used to support a raft-dependent mechanism.

lipid raft facilitation of FcγRIII-mediated phagocytosisFcRγ tyrosine phosphorylation downstream of IgG immune complex crosslinkinglipid depletionsterol repletionphotoswitchable sphingomyelin perturbationphagocytosis assayphosphorylation readout

Stages

  1. 1.
    Membrane lipid depletion perturbation(functional_characterization)

    This stage establishes whether cholesterol and sphingomyelin are required for efficient IgG-mediated phagocytosis before testing rescue or mechanistic signaling consequences.

    Selection: Test whether cholesterol or sphingomyelin depletion impairs IgG-mediated phagocytosis.

  2. 2.
    Sterol repletion comparison(secondary_characterization)

    This stage tests whether restoring or opposing raft-promoting sterol properties changes phagocytosis in the predicted direction.

    Selection: Compare raft-promoting 7-dehydrocholesterol with raft-inhibiting coprostanol for effects on phagocytosis after perturbation.

  3. 3.
    Photoswitchable sphingomyelin test(secondary_characterization)

    This stage provides an orthogonal and reversible membrane perturbation test of the raft-dependence hypothesis.

    Selection: Use AzoSM to compare raft-promoting trans and raft-inhibiting cis conformations for phagocytosis effects.

  4. 4.
    FcRγ phosphorylation readout(confirmatory_validation)

    This stage tests whether the same membrane perturbations that alter phagocytosis also alter a proximal FcγR signaling event.

    Selection: Measure FcRγ phosphorylation after membrane perturbations to connect phagocytosis effects to FcγR signaling.

Taxonomy & Function

Primary hierarchy

Mechanism Branch

Component: A low-level RNA part used inside a larger architecture that realizes a mechanism.

Techniques

No technique tags yet.

Target processes

No target processes tagged yet.

Input: Light

Implementation Constraints

cofactor dependency: cofactor requirement unknownencoding mode: genetically encodedimplementation constraint: context specific validationimplementation constraint: spectral hardware requirementoperating role: actuator

Its use requires macrophage cells and the AzoSM reagent in defined conformational states. The abstract implies an experimental setup that can compare trans-AzoSM and cis-AzoSM effects on phagocytosis.; requires use of the photoswitchable sphingomyelin reagent and control of its trans versus cis conformation

The abstract does not show that AzoSM is a general-purpose therapeutic or that it resolves all mechanisms downstream of FcγR signaling.; the abstract supports use in this macrophage phagocytosis context only

Validation

Cell-freeBacteriaMammalianMouseHumanTherapeuticIndep. Replication

Supporting Sources

Ranked Claims

Claim 1tool behaviorsupports2021Source 1needs review

AzoSM reports raft-state dependence of phagocytosis, with trans-AzoSM supporting efficient phagocytosis and cis-AzoSM significantly but reversibly blunting phagocytosis.

Approval Evidence

1 source1 linked approval claimfirst-pass slug azosm
Using a photoswitchable SM (AzoSM), we observed that the raft-promoting conformation (trans-AzoSM) resulted in efficient phagocytosis, whereas the raft-inhibiting conformation (cis-AzoSM) significantly but reversibly blunted phagocytosis.

Source:

tool behaviorsupports

AzoSM reports raft-state dependence of phagocytosis, with trans-AzoSM supporting efficient phagocytosis and cis-AzoSM significantly but reversibly blunting phagocytosis.

Source:

Comparisons

Source-stated alternatives

The paper contrasts AzoSM-based membrane perturbation with sterol repletion using 7-dehydrocholesterol or coprostanol.

Source:

The paper contrasts AzoSM-based membrane perturbation with sterol repletion using 7-dehydrocholesterol or coprostanol.

Source-backed strengths

supports reversible comparison of raft-promoting and raft-inhibiting membrane states within the same chemical framework

Source:

supports reversible comparison of raft-promoting and raft-inhibiting membrane states within the same chemical framework

Compared with phosphorothioate-caged antisense oligonucleotides

AzoSM and phosphorothioate-caged antisense oligonucleotides address a similar problem space.

Shared frame: same top-level item type; same primary input modality: light

Compared with photo-sensitive circular gRNAs

AzoSM and photo-sensitive circular gRNAs address a similar problem space.

Shared frame: same top-level item type; same primary input modality: light

Compared with RNA aptamer

AzoSM and RNA aptamer address a similar problem space.

Shared frame: same top-level item type; same primary input modality: light

Ranked Citations

  1. 1.
    StructuralSource 1Journal of Biological Chemistry2021Claim 1

    Extracted from this source document.