NAPB Antibodies

Structure of NAPB

NAPB is a medium-sized nuclear protein with a molecular weight of approximately 45-50kDa, and there are certain differences among different species. The following is a comparison of the characteristics of NAPB proteins in the main species:

NAPB is composed of about 400 amino acids, protein has the characteristic of dimer structure, protein surface with large positive charge, this allows it to effectively combine with negatively charged DNA. The conserved acidic amino acid region is crucial for maintaining protein stability, while the variable region determines species-specific functional differences. Secondary structure analysis shows that NAPB contains approximately 60% α -helix and 15% β -fold. This conformation provides a structural basis for its nucleosome assembly function.

Fig. 1 Stepwise Chromatin Assembly Model: NAP-1 Mediated Histone Transfer and ACF-Dependent Maturation.¹

Key structural properties of NAPB:

• Characteristic dimer structure
• Positively charged protein surfaces facilitate DNA binding
• Conservative acidic amino acid area to maintain stability
• Variable regions determine species-specific functions

Functions of NAPB

NAPB's core function is to participate in nucleosome assembly and chromatin remodeling, and it plays a key role in multiple cellular processes at the same time:

NAPB interact with the DNA of the present collaborative combined with the characteristics, the combined type in an s-shaped curve, show that multiple NAPB molecules can form on chromatin complex function. This characteristic enables it to efficiently regulate the structural state of large chromatin regions.

Applications of NAPB and NAPB Antibody in Literature

1. Nakagawa, Takeya, et al. "Multistep chromatin assembly on supercoiled plasmid DNA by nucleosome assembly protein-1 and ATP-utilizing chromatin assembly and remodeling factor." Journal of Biological Chemistry 276.29 (2001): 27384-27391. https://doi.org/10.1074/jbc.M101331200

This study reveals the synergistic mechanism of nucleosome assembly protein 1 (NAP-1) and chromatin remodeling factor ACF in nucleosome assembly in vitro. Studies have found that NAP-1 has a high affinity for H2A-H2B histones, can effectively deposit them onto the supercoiled DNA template, and complete histone transfer in the presence of H3-H4. The ACF is responsible for the precise positioning and spacing control of nucleosomes. Even if added later, it can form a regularly arranged nucleosome array. Atomic force microscopy observations confirmed that NAP-1 alone cannot form fine nucleosome core particles and must act in synergy with ACF. These findings provide a new model for understanding the ordered deposition of histones and the arrangement of nucleosomes during chromatin assembly in vivo.

2. Ishimi, Yukio, and Akihiko Kikuchi. "Identification and molecular cloning of yeast homolog of nucleosome assembly protein I which facilitates nucleosome assembly in vitro." Journal of Biological Chemistry 266.11 (1991): 7025-7029. https://doi.org/10.1016/S0021-9258(20)89604-5

In this study, the yeast nucleosome assembly protein I (NAP-I) gene was successfully cloned and identified. The 60kDa protein encoded by it has similar functions to human and mouse NAP-I. This protein contains three negatively charged regions (rich in glutamic acid and aspartic acid), which may mediate the interaction with histones. Western blotting revealed that NAP-I was ubiquitous in clawing toad oocytes and drosophilofruit culture cells, suggesting its conserved function in chromatin assembly. The research provides new clues for understanding the synergistic effect between NAP-I and other nucleosome assembly proteins.

3. Tóth, Katalin Fejes, Jacek Mazurkiewicz, and Karsten Rippe. "Association states of nucleosome assembly protein 1 and its complexes with histones." Journal of Biological Chemistry 280.16 (2005): 15690-15699. https://doi.org/10.1074/jbc.M413329200

This study reveals that the histone chaperone NAP1 regulates nucleosome assembly through dimer/octamer dynamic equilibrium. Analysis of ultracentrifugation revealed that under physiological conditions, NAP1 exists in the form of dimers and octamers and binds to histones in a 1:1 stoichiometric ratio. Especially during the S phase, NAP1 octamer can act as a multi-histone carrier to promote the new assembly of chromatin. This discovery clarifies the functional transition mechanism of NAP1 in the cell cycle.

4. Mazurkiewicz, Jacek, J. Felix Kepert, and Karsten Rippe. "On the mechanism of nucleosome assembly by histone chaperone NAP1." Journal of Biological Chemistry 281.24 (2006): 16462-16472. https://doi.org/10.1074/jbc.M511619200

This study quantitatively reveals the three-step nucleosome assembly mechanism mediated by the histone chaperone NAP1: First, the H3-H4 tetramer is formed (k1=2.5×10⁴), then the first H2A-H2B is rapidly assembled to form the htrimer (k2=4.1×10⁵), and finally the second H2A-H2B is added to complete the assembly (k3=6.6×10³). The research found that H2A.Z affects the stability of nucleosomes, and NAP1 can mediate H1 binding (k4=7.7×10³), while ACF does not accelerate this process.

5. Fujii-Nakata, T., et al. "Functional analysis of nucleosome assembly protein, NAP-1. The negatively charged COOH-terminal region is not necessary for the intrinsic assembly activity." Journal of Biological Chemistry 267.29 (1992): 20980-20986. https://doi.org/10.1016/s0021-9258(19)36785-7

This study determined that the 43-365 amino acid region of the NAP-1 protein of Saccharomyces cerevisiae is the key domain of its nucleosome assembly activity. This segment can form a functional 12S complex, while the C-terminal negative charge region is not essential. The study clarified the structural basis of NAP-1 mediating the binding of histones to DNA.

Creative Biolabs: NAPB Antibodies for Research

Creative Biolabs specializes in the production of high-quality NAPB antibodies for research and industrial applications. Our portfolio includes monoclonal antibodies tailored for Western blot, co-immunoprecipitation (Co-IP), immunofluorescence (IF), and other advanced techniques, providing reliable solutions for chromatin structure and function studies.

• Custom NAPB Antibody Development: Tailor-made solutions to meet specific research requirements.
• Bulk Production: Large-scale antibody manufacturing for industry partners.
• Technical Support: Expert consultation for protocol optimization and troubleshooting.
• Aliquoting Services: Conveniently sized aliquots for long-term storage and consistent experimental outcomes.

For more details on our NAPB antibodies, custom preparations, or technical support, contact us at info@creative-biolabs.com.