Information Hiding Based on DNA Sequences

يعد أمن المعلومات مصدر قلق رئيسي، خاصة في ضوء التوسع السريع في استخدام الإنترنت في السنوات الأخيرة. نتيجة لهذا التوسع، كانت هناك حالات وصول غير قانوني، والتي تم تخفيفها من خلال اعتماد مجموعة متنوعة من بروتوكولات الاتصال الآمن، بما في ذلك التشفير وإخفاء البيانات. في السنوات الأخيرة، كانت هناك زيادة في استخدام الحمض النووي للتشفير وإخفاء البيانات كناقل، مع الاستفادة من قدراته الجزيئية الحيوية. في إخفاء البيانات. نتيجة لذلك، في نهج إخفاء البيانات، يتم استخدام قواعد الحمض النووي كناقل للمعلومات لتعزيز الأمن. يندمج علم إخفاء المعلومات والتشفير المستند إلى الحمض النووي بين السمات البيولوجية والتقنيات التقليدية من أجل تحقيق خوارزمية مؤمنة جيدًا تستغلها. لذلك، توفر تسلسلات الحمض النووي قدرة عالية على البيانات بما في ذلك الحفاظ على الخصائص الكيميائية والبيولوجية لتسلسل الحمض النووي.Information security is a major source of worry, especially in light of the rapid expansion of internet use in recent years. As a result of this expansion, there have been incidences of illegal access, which have been mitigated by the adoption of a variety of secure communication protocols, including encryption and data concealment. DNA's bio-molecular properties have seen an uptick in popularity as a carrier for cryptography and data hiding in recent years. when information needs to be hidden. Therefore, DNA bases are utilized as information carriers in the data concealing strategy to increase safety. DNA-based steganography and cryptography combine a biological property with conventional methods to provide an algorithm with increased security. Because of their ability to maintain their chemical and biological characteristics, DNA sequences also have a high data capacity

Regulation of Translesion Synthesis DNA Polymerase η by Monoubiquitination

DNA polymerase eta is a Y family polymerase involved in translesion synthesis (TLS). Its action is initiated by simultaneous interaction between the PIP box in pol eta and PCNA and between the UBZ in pol eta and monoubiquitin attached to PCNA. Whereas monoubiquitination of PCNA is required for its interaction with pol eta during TLS, we now show that monoubiquitination of pol eta inhibits this interaction, preventing its functions in undamaged cells. Identification of monoubiquitination sites within pol eta nuclear localization signal (NLS) led to the discovery that pol eta NLS directly contacts PCNA, forming an extended pol eta-PCNA interaction surface. We name this the PCNA-interacting region (PIR) and show that its monoubiquitination is downregulated by various DNA-damaging agents. We propose that this mechanism ensures optimal availability of nonubiquitinated, TLS-competent pol eta after DNA damage. Our work shows how monoubiquitination can either positively or negatively regulate the assembly of a protein complex, depending on which substrates are targeted by ubiquitin

TF2Network : predicting transcription factor regulators and gene regulatory networks in Arabidopsis using publicly available binding site information

A gene regulatory network (GRN) is a collection of regulatory interactions between transcription factors (TFs) and their target genes. GRNs control different biological processes and have been instrumental to understand the organization and complexity of gene regulation. Although various experimental methods have been used to map GRNs in Arabidop-sis thaliana, their limited throughput combined with the large number of TFs makes that for many genes our knowledge about regulating TFs is incomplete. We introduce TF2Network, a tool that exploits the vast amount of TF binding site information and enables the delineation of GRNs by detecting potential regulators for a set of co-expressed or functionally related genes. Validation using two experimental benchmarks reveals that TF2Network predicts the correct regulator in 75-92% of the test sets. Furthermore, our tool is robust to noise in the input gene sets, has a low false discovery rate, and shows a better performance to recover correct regulators compared to other plant tools. TF2Network is accessible through a web interface where GRNs are interactively visualized and annotated with various types of experimental functional information. TF2Network was used to perform systematic functional and regulatory gene annotations, identifying new TFs involved in circadian rhythm and stress response

ROI-based reversible watermarking scheme for ensuring the integrity and authenticity of DICOM MR images

Reversible and imperceptible watermarking is recognized as a robust approach to confirm the integrity and authenticity of medical images and to verify that alterations can be detected and tracked back. In this paper, a novel blind reversible watermarking approach is presented to detect intentional and unintentional changes within brain Magnetic Resonance (MR) images. The scheme segments images into two parts; the Region of Interest (ROI) and the Region of Non Interest (RONI). Watermark data is encoded into the ROI using reversible watermarking based on the Difference Expansion (DE) technique. Experimental results show that the proposed method, whilst fully reversible, can also realize a watermarked image with low degradation for reasonable and controllable embedding capacity. This is fulfilled by concealing the data into ‘smooth’ regions inside the ROI and through the elimination of the large location map required for extracting the watermark and retrieving the original image. Our scheme delivers highly imperceptible watermarked images, at 92.18-99.94dB Peak Signal to Noise Ratio (PSNR) evaluated through implementing a clinical trial based on relative Visual Grading Analysis (relative VGA). This trial defines the level of modification that can be applied to medical images without perceptual distortion. This compares favorably to outcomes reported under current state-of-art techniques. Integrity and authenticity of medical images are also ensured through detecting subsequent changes enacted on the watermarked images. This enhanced security measure, therefore, enables the detection of image manipulations, by an imperceptible approach, that may establish increased trust in the digital medical workflow