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Topic Review
Potocki-Lupski Syndrome
Potocki-Lupski syndrome is a condition that results from having an extra copy (duplication) of a small piece of chromosome 17 in each cell. The duplication occurs on the short (p) arm of the chromosome at a position designated p11.2. This condition is also known as 17p11.2 duplication syndrome.
  • 1.5K
  • 24 Dec 2020
Topic Review
Conservation in South African Indigenous Goat Ecotypes
Goats were amongst the first livestock to be domesticated more than 10,000 years ago for their meat, milk, skin, and fiber. They were introduced to Southern Africa by migrating nations from Central Africa to the south. Due to local adaptation to the different agro-ecological zones and selection, indigenous goats are identified as ecotypes within the indigenous veld goat breed. Their ability to thrive in a resource-limited production system and in challenging environmental conditions makes them valuable animal resources for small-scale and emerging farmers. They play important roles in household agriculture and cultural activities as well as in poverty alleviation. 
  • 1.5K
  • 09 Dec 2022
Topic Review
Zona Pellucida
All mammalian oocytes and eggs are surrounded by a relatively thick extracellular matrix (ECM), the zona pellucida (ZP), that plays vital roles during oogenesis, fertilization, and preimplantation development. Unlike ECM surrounding somatic cells, the ZP is composed of only a few glycosylated proteins, ZP1–4, that are unique to oocytes and eggs. ZP1–4 have a large region of polypeptide, the ZP domain (ZPD), consisting of two subdomains, ZP-N and ZP-C, separated by a short linker region, that plays an essential role in polymerization of nascent ZP proteins into crosslinked fibrils. Both subdomains adopt immunoglobulin (Ig)-like folds for their 3-dimensional structure. Mouse and human ZP genes are encoded by single-copy genes located on different chromosomes and are highly expressed in the ovary by growing oocytes during late stages of oogenesis. Genes encoding ZP proteins are conserved among mammals, and their expression is regulated by cis-acting sequences located close to the transcription start-site and by the same/similar trans-acting factors. Nascent ZP proteins are synthesized, packaged into vesicles, secreted into the extracellular space, and assembled into long, crosslinked fibrils that have a structural repeat, a ZP2-ZP3 dimer, and constitute the ZP matrix. Fibrils are oriented differently with respect to the oolemma in the inner and outer layers of the ZP. Sequence elements in the ZPD and the carboxy-terminal propeptide of ZP1–4 regulate secretion and assembly of nascent ZP proteins. The presence of both ZP2 and ZP3 is required to assemble ZP fibrils and ZP1 and ZP4 are used to crosslink the fibrils. Inactivation of mouse ZP genes by gene targeting has a detrimental effect on ZP formation around growing oocytes and female fertility. Gene sequence variations in human ZP genes due to point, missense, or frameshift mutations also have a detrimental effect on ZP formation and female fertility. The latter mutations provide additional support for the role of ZPD subdomains and other regions of ZP polypeptide in polymerization of human ZP proteins into fibrils and matrix. 
  • 1.5K
  • 10 Sep 2021
Topic Review
Elovl4 genes in Sparus aurata
Very long-chain (˃C24) fatty acids (VLC-FA) play critical roles during early development of vertebrates, since these compounds are accumulated in the rapidly forming neural tissues, ensuring their normal function. However, despite their putative importance, the study of VLC-FA in fish is scarce. Biosynthesis of VLC-FA is carried out by the so-called elongation of very long-chain fatty acid 4 (Elovl4) proteins and, consequently, the complement and function of these enzymes determine the capacity that a given species has for satisfying the physiological demands for VLC-FA, especially during its early development. The present study aimed to characterize elovl4 genes from the marine teleosts Sparus aurata and Solea senegalensis, and determine the function of the corresponding encoded proteins. Moreover, the tissue expression pattern of elovl4 genes was determined. The results confirmed that both fish species possess two distinct Elovl4 proteins termed as Elovl4a and Elovl4b based on their homology to the zebrafish orthologs. Functional assays in yeast denoted that both Elovl4a and Elovl4b from both species had the capability to elongate C20-24 fatty acid precursors to VLC-FA products. However, Elovl4b appeared to have a higher activity than Elovl4a elongating all the polyunsaturated fatty acid substrates assayed to longer chain polyunsaturated products, especially on the n-3 series. Gene expression results indicated that, although elovl4 transcripts were detected in most tissues analyzed, elovl4 genes were more strongly expressed in both species neural tissues such as brain and eyes, which showed the highest expression levels of elovl4a and elovl4b, respectively. These results are consistent with the functions of Elovl4 from other vertebrates. Importantly, these findings contribute to a better understanding of the VLC-FA biosynthetic pathway in marine teleosts, highlighting the crucial role that Elovl4 products carry out for the correct development and maintenance of neurophysiologic functions during early stages of the fish development.
  • 1.5K
  • 28 Oct 2020
Topic Review
R-Loops and Its Chro-Mates
R-loops have been associated with both physiological and pathological functions that are conserved across species. R-loops are a source of replication stress and genome instability, as seen in neurodegenerative disorders and cancer. In response, cells have evolved pathways to prevent R-loop accumulation as well as to resolve them. This review covers various mechanisms precluding R‐loop accumulation and highlights the role of Chro-Mates (chromatin modifiers and remodelers) in facilitating timely R‐loop resolution. We also discuss the enigmatic role of RNA:DNA hybrids in facilitating DNA repair, epigenetic landscape and the potential role of replication fork preservation pathways, active fork stability and stalled fork protection pathways, in avoiding replication-transcription conflicts. 
  • 1.5K
  • 02 Sep 2021
Topic Review
Genetic and Molecular Basis of Von Hippel-Lindau Disease
Von Hippel-Lindau disease (VHL disease or VHL syndrome) is a familial multisystem neoplastic disorder, stemming from germline disease-associated variants of the VHL tumor suppressor gene. VHL protein is involved in oxygen sensing and adaptive response to hypoxia through the EPO-VHL-HIF signaling axis. In recent years, numerous HIF-independent pathways of VHL have been identified, expanding the role of VHL throughout several cellular processes. In addition to VHL syndrome-associated tumors, VHL variations have also been associated with the development of eythrocytosis. Research indicated that there is a distinction between erythrocytosis-causing VHL variations and VHL variations causing VHL disease with tumor development. Therefore, elucidating the molecular background of the pathogenic effects of VHL variants could help determine the best approach to VHL disease management.  
  • 1.5K
  • 24 Mar 2022
Topic Review
Mitochondrial DNA and DOHaD
Mitochondrial dysfunction is known to contribute to mitochondrial diseases, as well as to a variety of aging-based pathologies. Mitochondria have their own genomes (mitochondrial DNA (mtDNA)) and the abnormalities, such as point mutations, deletions, and copy number variations, are involved in mitochondrial dysfunction. In recent years, several epidemiological studies and animal experiments have supported the Developmental Origin of Health and Disease (DOHaD) theory, which states that the environment during fetal life influences the predisposition to disease and the risk of morbidity in adulthood. Mitochondria play a central role in energy production, as well as in various cellular functions, such as apoptosis, lipid metabolism, and calcium metabolism.
  • 1.5K
  • 19 Jul 2021
Topic Review
MT-ND5 Gene
mitochondrially encoded NADH:ubiquinone oxidoreductase core subunit 5
  • 1.5K
  • 23 Dec 2020
Topic Review
CBF-AML
Core binding factor acute myeloid leukemia (CBF-AML) is one form of a cancer of the blood-forming tissue (bone marrow) called acute myeloid leukemia. In normal bone marrow, early blood cells called hematopoietic stem cells develop into several types of blood cells: white blood cells (leukocytes) that protect the body from infection, red blood cells (erythrocytes) that carry oxygen, and platelets (thrombocytes) that are involved in blood clotting. In acute myeloid leukemia, the bone marrow makes large numbers of abnormal, immature white blood cells called myeloid blasts. Instead of developing into normal white blood cells, the myeloid blasts develop into cancerous leukemia cells. The large number of abnormal cells in the bone marrow interferes with the production of functional white blood cells, red blood cells, and platelets.
  • 1.5K
  • 04 Jan 2021
Topic Review
Prenatal Detection of Uniparental Disomies
Prenatal detection of uniparental disomy (UPD) is a methodological challenge, and a positive testing result requires comprehensive considerations on the clinical consequences as well as ethical issues.
  • 1.5K
  • 21 Dec 2020
Topic Review
Tourette Syndrome
Tourette syndrome is a complex disorder characterized by repetitive, sudden, and involuntary movements or noises called tics. Tics usually appear in childhood, and their severity varies over time. In most cases, tics become milder and less frequent in late adolescence and adulthood.  
  • 1.5K
  • 23 Dec 2020
Topic Review
Bannayan-Riley-Ruvalcaba Syndrome
Bannayan-Riley-Ruvalcaba syndrome is a genetic condition characterized by a large head size (macrocephaly), multiple noncancerous tumors and tumor-like growths called hamartomas, and dark freckles on the penis in males. The signs and symptoms of Bannayan-Riley-Ruvalcaba syndrome are present from birth or become apparent in early childhood.
  • 1.5K
  • 24 Dec 2020
Topic Review
PHARC Syndrome
PHARC (polyneuropathy, hearing loss, ataxia, retinitis pigmentosa (RP) and early-onset cataract) is an acronym for a rare, neurodegenerative disease caused by biallelic variants in the ABHD12 gene
  • 1.5K
  • 12 Oct 2021
Topic Review
HANAC
Hereditary angiopathy with nephropathy, aneurysms, and muscle cramps (HANAC) syndrome is part of a group of conditions called the COL4A1-related disorders. The conditions in this group have a range of signs and symptoms that involve fragile blood vessels. HANAC syndrome is characterized by angiopathy, which is a disorder of the blood vessels. In people with HANAC syndrome, angiopathy affects several parts of the body. The blood vessels as well as thin sheet-like structures called basement membranes that separate and support cells are weakened and more susceptible to breakage.
  • 1.5K
  • 04 Jan 2021
Topic Review
CFTR Gene
Cystic fibrosis transmembrane conductance regulator
  • 1.5K
  • 04 Jan 2021
Topic Review
Ataxia Telangiectasia Mutated
ATM is among of the most critical initiators and coordinators of the DNA-damage response. ATM canonical and non-canonical signaling pathways involve hundreds of downstream targets that control many important cellular processes such as DNA damage repair, apoptosis, cell cycle arrest, metabolism, proliferation, oxidative sensing, among others. Of note, ATM is often considered a major tumor suppressor because of its ability to induce apoptosis and cell cycle arrest. However, in some advanced stage tumor cells, ATM signaling is increased and confers remarkable advantages for cancer cell survival, resistance to radiation and chemotherapy, biosynthesis, proliferation, and metastasis. 
  • 1.5K
  • 02 Jun 2021
Topic Review
Satellite DNA of primate genome
Satellite DNA (satDNA) is defined as highly repetitive DNA consisting of short sequences tandemly repeated a large number of times. Collectively known as the "satellitome", this genomic component offers exciting evolutionary insights into aspects of primate genome biology that raise new questions and challenge existing paradigms. 
  • 1.4K
  • 25 Jan 2021
Topic Review
DNA-Dependent Protein Kinase
The DNA-dependent protein kinase (DNA-PK) is composed of a DNA-dependent protein kinase catalytic subunit (DNA-PKcs) and Ku70/Ku80 heterodimer. DNA-PK is thought to act as the “sensor” for DNA double-stranded breaks (DSB), which are considered the most deleterious type of DNA damage. In particular, DNA-PKcs and Ku are shown to be essential for DSB repair through nonhomologous end joining (NHEJ). The phenotypes of animals and human individuals with defective DNA-PKcs or Ku functions indicate their essential roles in these developments, especially in neuronal and immune systems. DNA-PKcs are structurally related to Ataxia–telangiectasia mutated (ATM), which is also implicated in the cellular responses to DSBs. DNA-PKcs and ATM constitute the phosphatidylinositol 3-kinase-like kinases (PIKKs) family with several other molecules.
  • 1.4K
  • 11 Oct 2021
Topic Review
High-resolution melt method
HRM (High-resolution melt) analysis is a powerful molecular biology detection method used for the identification of genetic mutations, DNA methylation analysis or species identification. 
  • 1.4K
  • 27 Oct 2020
Topic Review
ADLD
Autosomal dominant leukodystrophy with autonomic disease (ADLD) is one of a group of genetic disorders called leukodystrophies. Leukodystrophies are characterized by abnormalities of the nervous system's white matter, which consists of nerve fibers covered by a fatty substance called myelin. Myelin insulates and protects nerve fibers and promotes the rapid transmission of nerve impulses.
  • 1.4K
  • 04 Jan 2021
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