Related Experiment Video

Updated: Aug 15, 2025

Examining BCL-2 Family Function with Large Unilamellar Vesicles
08:35

Examining BCL-2 Family Function with Large Unilamellar Vesicles

Published on: October 5, 2012

8.0K

Effect of UV Stress on the Structure and Function of Pro-apoptotic Bid and Anti-apoptotic Bcl-xl proteins

Akash Bera1, Suraj Singh1, Jacinta S D'Souza2

  • 1Department of Biophysics, University of Mumbai Santacruz (E) Kalina, Mumbai, 400101, India.

Chembiochem : a European Journal of Chemical Biology
|January 3, 2023
PubMed

Insights

Ultraviolet C (UV-C) radiation alters the structure and function of key apoptosis-regulating proteins, Bcl-xlΔC and Bid-FL. Bcl-xlΔC, more sensitive to UV-C, shows reduced interaction with tBid.

Area of Science:

  • Molecular Biology
  • Cellular Biology
  • Biophysics

Background:

  • Ultraviolet C (UV-C) radiation triggers apoptosis in mammalian cells through the mitochondrion-mediated pathway.
  • The Bcl-2 family of proteins regulates this pathway and is responsive to UV-C radiation.
  • The direct impact of UV-C on the structure and function of these regulatory proteins remains unclear.

Purpose of the Study:

  • To investigate the effects of UV-C irradiation on the structure and function of pro-apoptotic Bid-FL and anti-apoptotic Bcl-xlΔC proteins.
  • To determine the relative sensitivity of Bcl-xlΔC and Bid-FL to UV-C-induced structural changes.
  • To elucidate the functional consequences of UV-C-induced structural alterations on protein interactions.

Main Methods:

  • Utilized a suite of biophysical techniques to analyze protein structure and function.
  • Investigated UV-C irradiation effects on purified Bcl-xlΔC and Bid-FL proteins.
  • Assessed changes in protein structure, including secondary structure elements and binding interactions.

Main Results:

  • UV-C irradiation caused irreversible structural alterations in both Bcl-xlΔC and Bid-FL.
  • Bcl-xlΔC exhibited higher sensitivity to UV-C stress compared to Bid-FL.
  • UV-C exposure induced significant structural perturbations (α-helix to β-sheet) in the BH3-binding region of Bcl-xlΔC.
  • UV-exposed Bcl-xlΔC demonstrated reduced efficacy in interacting with pro-apoptotic tBid.

Conclusions:

  • UV-C radiation directly impacts the structure and function of critical Bcl-2 family proteins.
  • The observed structural changes in Bcl-xlΔC, particularly in the BH3-binding region, impair its interaction with tBid.
  • These findings provide insights into the molecular mechanisms by which UV-C radiation affects apoptosis regulation.
Keywords:
Bcl-xlBidNMR spectroscopyUV-Capoptosis

More Related Videos

Applying an Inducible Expression System to Study Interference of Bacterial Virulence Factors with Intracellular Signaling08:51

Applying an Inducible Expression System to Study Interference of Bacterial Virulence Factors with Intracellular Signaling

Published on: June 25, 2015

9.3K
Identifying Protein-protein Interaction Sites Using Peptide Arrays07:44

Identifying Protein-protein Interaction Sites Using Peptide Arrays

Published on: November 18, 2014

18.1K

Related Concept Videos

The Intrinsic Apoptotic Pathway01:31

The Intrinsic Apoptotic Pathway

Internal cellular stress, such as cellular injury or hypoxia, triggers intrinsic apoptosis. The B-cell lymphoma 2 (Bcl-2) family of proteins are the primary regulators of the intrinsic apoptotic pathway. For example, during DNA damage, checkpoint proteins, such as Ataxia Telangiectasia Mutated (ATM protein) and Checkpoints Factor-2 (Chk2) proteins, are activated. These proteins phosphorylate p53 which further activates pro-apoptotic proteins, such as Bax, Bak, PUMA, and Noxa, and inhibits...
6.7K
The Extrinsic Apoptotic Pathway01:17

The Extrinsic Apoptotic Pathway

The extrinsic apoptotic pathway is initiated when extracellular death-inducing signals, such as specific cytokines, activate the death receptors expressed on the cell surface. The immune cells involved in this pathway are natural killer cells (NK cells) and cytotoxic T-lymphocytes. NK cells are critical in innate immune response, while cytotoxic T-lymphocytes are associated with adaptive immune response. These cells recognize specific receptors expressed on the altered cells and activate...
6.5K
Caspases01:24

Caspases

Caspase, a family of cysteine proteases, serve as effectors in apoptosis. The ced3 gene in C.elegans was first identified to be involved in apoptosis. This gene encodes the ced-3 caspase that is similar to the interleukin-1-beta converting enzyme or ICE in mammals. In addition to apoptosis, caspases also function in the inflammatory response. Inflammatory caspases are essential in activating pro-inflammatory cytokines that recruit immune cells and block the replication of pathogens inside...
12.6K
Regulation of the Unfolded Protein Response01:31

Regulation of the Unfolded Protein Response

Inositol-requiring kinase one or IRE1 is the most conserved eukaryotic unfolded protein response (UPR) receptor. It is a type I transmembrane protein kinase receptor with a distinctive site-specific RNase activity. As the binding mechanics of the misfolded proteins with the N-terminal domain of IRE-1 are unclear, three binding models — direct, indirect, and allosteric -- are proposed for receptor activation. Nevertheless, it is known that once a misfolded protein associates with IRE1, it...
2.5K
Abnormal Proliferation02:23

Abnormal Proliferation

Under normal conditions, most adult cells remain in a non-proliferative state unless stimulated by internal or external factors to replace lost cells. Abnormal cell proliferation is a condition in which the cell's growth exceeds and is uncoordinated with normal cells. In such situations, cell division persists in the same excessive manner even after cessation of the stimuli, leading to persistent tumors. The tumor arises from the damaged cells that replicate to pass the damage to the...
4.6K
DNA Damage can Stall the Cell Cycle02:37

DNA Damage can Stall the Cell Cycle

In response to DNA damage, cells can pause the cell cycle to assess and repair the breaks. However, the cell must check the DNA at certain critical stages during the cell cycle. If the cell cycle pauses before DNA replication, the cells will contain twice the amount of DNA. On the other hand, if cells arrest after DNA replication but before mitosis, they will contain four times the normal amount of DNA. With a host of specialized proteins at their disposal,cells must use the right protein at...
9.3K