RESEARCH: AAA-PROTEIN-SUPERFAMILY
FOLDING PROJECT #19324 PROFILE

This project explores how Rubisco activase (Rca), a protein essential for plant growth, binds and uses energy from ATP to do its job. Scientists will use computer simulations to understand the exact steps involved in this process, identifying key parts of the Rca protein that are crucial for binding ATP.

Atomistic insights into AAA+ protein superfamily ATPases Associated with diverse cellular Activities (AAA+) comprise a superfamily of proteins that perform a large variety of functions essential to cell physiology, including control of protein homeostasis, DNA replication, recombination, chromatin remodeling, ribosomal RNA processing, molecular targeting, organelle biogenesis, and membrane fusion.

Members of this superfamily are defined by the presence of what is termed the AAA+ domain containing the canonical Walker A and B motifs required for ATP binding and hydrolysis.

Typically, genomes encode approximately ten to several hundred AAA+ family members, each of which is thought to be adapted to specific functional niches that necessitate precise mechanisms of substrate recognition and processing.

The striking adaptive radiation of AAA+ proteins to operate in diverse settings illustrates the versatile utility of the AAA+ domain.

AAA+ proteins typically form hexameric complexes and act as motors to remodel other proteins, DNA/RNA, or multicomponent complexes.

Indeed, many chaperones and ATP-dependent proteases are or have subunits that belong to this superfamily.

Rubisco activase (Rca) belongs to the AAA+ superfamily of proteins and it hydrolyzes ATP to ADP.

The complementarity of nucleotide-binding sites between AAA+ interfaces, the mechanism of ATP hydrolysis and the conformational changes activating or deactivating their ATP-binding pocket ensure a functional cycle that creates mechanical force to promote remodeling of substrates.

In this study, we will investigated the ADP/ATP and Mg2+ ion binding mechanism in Rca monomer and homodimers using extensive longtime scale simulations.

We will also try to find the binding pathway for ADP and ATP.

Simulations will also helps to predicts the crucial residues that involved in this binding process.

AAA+ protein

A superfamily of proteins with diverse cellular functions.

AAA+ proteins are a large group of proteins found in all living organisms. They play important roles in many cellular processes, such as DNA replication, protein folding, and cell division. These proteins are characterized by the presence of an AAA+ domain, which binds to ATP (energy currency of cells) and uses it to power various functions.

ATPases

Enzymes that hydrolyze ATP to ADP, releasing energy.

ATPases are enzymes that break down ATP (adenosine triphosphate), a molecule that cells use as energy. This process releases energy that can be used to power various cellular functions, such as muscle contraction, nerve impulse transmission, and protein synthesis.

Walker A and B motifs

Conserved amino acid sequences in ATP-binding proteins.

Walker A and B motifs are specific patterns of amino acids found within certain proteins. These motifs play a crucial role in binding to ATP (adenosine triphosphate), the energy currency of cells. They are essential for various cellular processes that require ATP hydrolysis, such as muscle contraction and signal transduction.

Rubisco activase (Rca)

A protein that activates Rubisco enzyme.

Rubisco activase (Rca) is an important enzyme found in plants. It plays a vital role in activating Rubisco, the key enzyme responsible for carbon fixation during photosynthesis. Rca helps to ensure efficient plant growth by facilitating the conversion of carbon dioxide into sugars.

ADP/ATP

Adenosine diphosphate and adenosine triphosphate.

ADP (adenosine diphosphate) and ATP (adenosine triphosphate) are molecules involved in energy transfer within cells. ATP is the primary energy currency of cells, while ADP is its lower-energy form. The conversion between ADP and ATP is essential for powering various cellular processes.

Mg2+

A magnesium ion.

Mg2+ (magnesium ion) is an essential mineral that plays a vital role in various biological processes. It acts as a cofactor for many enzymes, participates in DNA replication and repair, and helps regulate muscle function.