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Biology subjects

Kabir, M. R.

Publications and source records attributed to Kabir, M. R..

4 recordsLinked to original sources

ProtAttn-QuadNet: An attention-based deep learning framework for protein-protein interaction prediction using ProtBERT embeddings

Protein-protein interactions (PPIs) form the backbone of most cellular processes, governing signal transduction, gene regulation, and metabolic control. However, experimental approaches to identifying PPIs remain expensive, laborious, and often incomplete. Recent advances in protein language models (PLMs) have transformed sequence-based PPI prediction by enabling deep contextual encoding of biochemical and structural information directly from amino acid sequences. Building upon this progress, we present ProtAttn-QuadNet, an attention-based deep learning framework that leverages ProtBERT embeddings to model reciprocal dependencies between protein pairs. The proposed model employs a quad-stream attention mechanism that integrates individual protein features, synergistic interactions, and complementary differences through multi-level self- and cross-attention layers. This architecture enables the discovery of fine-grained relational patterns while ensuring balanced bidirectional modeling of interacting proteins. Evaluated on large-scale dataset from UniProt, ProtAttn-QuadNet achieves 97.16% accuracy (AUC-ROC 99.00%) on balanced data and 99.19% accuracy (AUC-ROC 99.76%) on oversampled datasets, surpassing several recent state-of-the-art PPI prediction methods. Statistical validation using the Chi-square and Wilcoxon signed-rank tests confirms the models predictive significance and reliability. ProtAttn-QuadNet offers a powerful computational framework for large-scale PPI prediction. Author summaryProteins work together to carry out almost every function in living cells, from sending signals to controlling metabolism. Knowing which proteins interact with each other helps scientists understand how cells work and how diseases develop. However, finding these interactions in the laboratory is often slow, costly, and incomplete. In this study, a computational model called ProtAttn-QuadNet is developed to predict protein-protein interactions using only the amino acid sequences of proteins. The model analyses each pair of proteins to find shared features and differences that indicate whether they interact. It also uses a set of attention layers that allow the model to focus on the most relevant sequence patterns. When tested on a large protein dataset, ProtAttn-QuadNet produced highly accurate and consistent results, performing better than several existing methods. These results suggest that ProtAttn-QuadNet can serve as a reliable tool for studying protein networks and may help guide future research in biology, medicine, and drug development.

bioinformatics↗

Path integration impairments reveal early cognitive changes in Subjective Cognitive Decline

Path integration, the ability to track ones position using self-motion cues, is critically dependent on the grid cell network in the entorhinal cortex, a region vulnerable to early Alzheimers disease pathology. In this study, we examined path integration performance in individuals with subjective cognitive decline (SCD), a group at increased risk for Alzheimers disease, and healthy controls using an immersive virtual reality task. We developed a Bayesian computational model to decompose path integration errors into distinct components. SCD participants exhibited significantly higher path integration error, primarily driven by increased memory leak, while other modelling-derived error sources, such as velocity gain, sensory and reporting noise, remained comparable across groups. Our findings suggest that path integration deficits, specifically memory leak, may serve as an early marker of neurodegeneration in SCD and highlight the potential of self-motion-based navigation tasks for detecting pre-symptomatic Alzheimers disease-related cognitive changes. TeaserVirtual reality, modelling, and plasma biomarkers reveal path integration deficits in pre-symptomatic Alzheimers vs normal aging.

neuroscience↗

Reinvestigation of grain weight genes TaTGW6 and OsTGW6 casts doubt on their role in auxin regulation in developing grains

The THOUSAND-GRAIN WEIGHT 6 genes (TaTGW6 and OsTGW6) are reported to result in larger grains of wheat and rice by reducing production of indole-3-acetic acid (IAA) in developing grains. However, a critical comparison of data on TaTGW6 and OsTGW6 with other reports on IAA synthesis in cereal grains requires that this hypothesis be reinvestigated. Here, we show that TaTGW6 and OsTGW6 are members of a large gene family that has undergone major, lineage-specific gene expansion. Wheat has nine genes, and rice three genes encoding proteins with more than 80% amino acid identity with TGW6 making it difficult to envisage how a single inactive allele could have a major effect on IAA levels. TGW6 is proposed to affect auxin levels by catalysing the hydrolysis of IAA-glucose (IAA-Glc). However, we show that developing wheat grains contain undetectable levels of ester IAA in comparison to free IAA and do not express an IAA-glucose synthase. Previous work on TGW6, reported maximal expression at 20 days after anthesis (DAA) in wheat and 2 DAA in rice. However, we show that neither gene is expressed in developing grains. Instead, TaTGW6, OsTGW6 and their close homologues are exclusively expressed in pre-emergence inflorescences; TaTGW6 is expressed particularly in microspores prior to mitosis. This combined with evidence for high levels of IAA production from tryptophan in developing grains demonstrates TaTGW6 and OsTGW6 cannot regulate grain size via the hydrolysis of IAA-Glc. Instead, their similarity to rice strictosidine synthase-like (OsSTRL2) suggests they play a key role in pollen development.

plant biology↗

Expression of TaTAR2.3-1B, TaYUC9-1 and TaYUC10 correlates with auxin and starch content of developing wheat grains

The role of auxin in developing grains of wheat (Triticum aestivum) is contentious with contradictory reports indicating either positive or negative effects of IAA (indole-3-acetic acid) on grain size. In addition, the contributions to the IAA pool from de novo synthesis via tryptophan, and from hydrolysis of IAA-glucose are unclear. Here we describe the first comprehensive study of tryptophan aminotransferase and indole-3-pyruvate mono-oxygenase expression during wheat grain development from 5 to 20 days after anthesis. A comparison of expression data with measurements of endogenous IAA via combined liquid chromatography-tandem mass spectrometry with heavy isotope labelled internal standards indicates that TaTAR2.3-1B, TaYUC9-A1, TaYUC9-B, TaYUC9-D1, TaYUC10-A and TaYUC10-D are primarily responsible for IAA production in developing grains. Furthermore, we show that IAA synthesis is controlled by genes expressed specifically in developing wheat grains as has already been reported in rice (Oryza sativa) and maize (Zea mays). Our results cast doubt on the proposed role of THOUSAND-GRAIN WEIGHT gene, TaTGW6, in promoting larger grain size via negative effects on grain IAA content. The work on TaTGW6 has overlooked the contribution of the dominant IAA biosynthesis pathway. Although IAA synthesis occurs primarily in the endosperm of wheat grains, we show that the TaYUC9-1 group is also strongly expressed in the embryo. Within the endosperm, TaYUC9-1 expression is highest in aleurone and transfer cells, supporting data from other cereals suggesting that IAA has a key role in differentiation of these tissues.

plant biology↗