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Layana, C.

Publications and source records attributed to Layana, C..

2 recordsLinked to original sources

Magnetic Affinity-Based Purification of His-Tagged Proteins Using Ni2+-Functionalized Nanoparticles

Recombinant protein purification is essential in many applications across industry, research, and biotechnology. The use of a histidine tag (His6) in affinity chromatography is the gold standard for purification. However, magnetic nanoparticles (MNPs) offer an excellent alternative due to their unique properties, such as rapid separation, superparamagnetism, and a high surface-to-volume ratio that facilitates nanoscale functionalization. MNPs provide a more efficient, faster, cost-effective, and sustainable method compared to traditional chromatography. In this work, we report the development and validation of a magnetic nanoparticle-based platform for the efficient, selective, and scalable purification of His6 recombinant proteins. The synthesized Ni2+-functionalized MNPs demonstrated high specificity for histidine-tagged proteins, as shown by the selective retention and imidazole-mediated elution of target proteins both from pre-purified samples and complex E. coli lysates. Comparative assays with bovine serum albumin and His6 protein A confirmed the selective affinity of the MNPs for His6. Furthermore, a scaled-up protocol using 4 mL of lysate yielded approximately 0.6 mg/mL of purified protein, doubling the output obtained via conventional immobilized metal affinity chromatography, while preserving purity. The simplicity, efficiency, and cost-effectiveness of this method render it a powerful tool for both analytical and preparative-scale protein purification, particularly in low-resource or high-throughput settings.

molecular biology↗

Distinct domains of Me31B interact with different eIF4E isoforms in the male germ line of Drosophila melanogaster

Eukaryotic translation initiation factor 4E (eIF4E) is a key factor involved in different aspects of mRNA metabolism. Drosophila melanogaster genome encodes eight eIF4E isoforms, and the canonical isoform eIF4E-1 is a ubiquitous protein that plays a key role in mRNA translation. eIF4E-3 is specifically expressed in testis and controls translation during spermatogenesis. In eukaryotic cells, translational control and mRNA decay is highly regulated in different cytoplasmic ribonucleoprotein foci, which include the processing bodies (PBs). In this study, we show that Drosophila eIF4E-1 and eIF4E-3 occur in PBs where might play a role in mRNA storage and translational repression. We also demonstrate that the DEAD-box RNA helicase Me31B, a component of PBs, physically interacts with eIF4E-1 and eIF4E-3 both in the yeast two-hybrid system and FRET in Drosophila S2 cells. Moreover, truncated and point mutated Me31B proteins indicate that the binding sites of Me31B for eIF4E-1 and eIF4E-3 are located in different domains. Residues Y401-L407 (at the carboxy-terminal) are essential for interaction with eIF4E-1, whereas residues F63-L70 (at the amino-terminal) are critical for interaction with eIF4E-3. Thus, Me31B represents a novel type of eIF4E-interacting protein. Our observations suggest that Me31B might recognize different eIF4E isoforms in different tissues, which could be the key to silencing specific messengers. They provide further evidence that alternative forms of eIF4E and their interactions with various partners add complexity to the control of gene expression in eukaryotes.

molecular biology↗