Adenylosuccinate Synthase: A carbon-nitrogen ligase. During purine ribonucleotide biosynthesis, this enzyme catalyzes the synthesis of adenylosuccinate from GTP; IMP; and aspartate with the formation of orthophosphate and GDP. EC 6.3.4.4.Adenylosuccinate Lyase: An enzyme that, in the course of purine ribonucleotide biosynthesis, catalyzes the conversion of 5'-phosphoribosyl-4-(N-succinocarboxamide)-5-aminoimidazole to 5'-phosphoribosyl-4-carboxamide-5-aminoimidazole and the conversion of adenylosuccinic acid to AMP. EC 4.3.2.2.Inosine Monophosphate: Inosine 5'-Monophosphate. A purine nucleotide which has hypoxanthine as the base and one phosphate group esterified to the sugar moiety.Purine-Pyrimidine Metabolism, Inborn ErrorsPurine Nucleotides: Purines attached to a RIBOSE and a phosphate that can polymerize to form DNA and RNA.Saccharomyces cerevisiae: A species of the genus SACCHAROMYCES, family Saccharomycetaceae, order Saccharomycetales, known as "baker's" or "brewer's" yeast. The dried form is used as a dietary supplement.Saccharomyces cerevisiae Proteins: Proteins obtained from the species SACCHAROMYCES CEREVISIAE. The function of specific proteins from this organism are the subject of intense scientific interest and have been used to derive basic understanding of the functioning similar proteins in higher eukaryotes.Hydroxymethyl and Formyl Transferases: Enzymes that catalyze the transfer of hydroxymethyl or formyl groups. EC 2.1.2.Haemophilus influenzae: A species of HAEMOPHILUS found on the mucous membranes of humans and a variety of animals. The species is further divided into biotypes I through VIII.Haemophilus Infections: Infections with bacteria of the genus HAEMOPHILUS.Haemophilus: A genus of PASTEURELLACEAE that consists of several species occurring in animals and humans. Its organisms are described as gram-negative, facultatively anaerobic, coccobacillus or rod-shaped, and nonmotile.Dual-Specificity Phosphatases: A sub-class of protein tyrosine phosphatases that contain an additional phosphatase activity which cleaves phosphate ester bonds on SERINE or THREONINE residues that are located on the same protein.MicroRNAs: Small double-stranded, non-protein coding RNAs, 21-25 nucleotides in length generated from single-stranded microRNA gene transcripts by the same RIBONUCLEASE III, Dicer, that produces small interfering RNAs (RNA, SMALL INTERFERING). They become part of the RNA-INDUCED SILENCING COMPLEX and repress the translation (TRANSLATION, GENETIC) of target RNA by binding to homologous 3'UTR region as an imperfect match. The small temporal RNAs (stRNAs), let-7 and lin-4, from C. elegans, are the first 2 miRNAs discovered, and are from a class of miRNAs involved in developmental timing.Streptomyces griseus: An actinomycete from which the antibiotics STREPTOMYCIN, grisein, and CANDICIDIN are obtained.3' Untranslated Regions: The sequence at the 3' end of messenger RNA that does not code for product. This region contains transcription and translation regulating sequences.Protein Tyrosine Phosphatases: An enzyme group that specifically dephosphorylates phosphotyrosyl residues in selected proteins. Together with PROTEIN-TYROSINE KINASE, it regulates tyrosine phosphorylation and dephosphorylation in cellular signal transduction and may play a role in cell growth control and carcinogenesis.Insectivora: An order of insect eating MAMMALS including MOLES; SHREWS; HEDGEHOGS and tenrecs.Cyclin-Dependent Kinases: Protein kinases that control cell cycle progression in all eukaryotes and require physical association with CYCLINS to achieve full enzymatic activity. Cyclin-dependent kinases are regulated by phosphorylation and dephosphorylation events.Metabolome: The dynamic collection of metabolites which represent a cell's or organism's net metabolic response to current conditions.Metabolomics: The systematic identification and quantitation of all the metabolic products of a cell, tissue, organ, or organism under varying conditions. The METABOLOME of a cell or organism is a dynamic collection of metabolites which represent its net response to current conditions.Inosine NucleotidesPoly I: A group of inosine ribonucleotides in which the phosphate residues of each inosine ribonucleotide act as bridges in forming diester linkages between the ribose moieties.Hypoxanthines: Purine bases related to hypoxanthine, an intermediate product of uric acid synthesis and a breakdown product of adenine catabolism.Abbreviations as Topic: Shortened forms of written words or phrases used for brevity.Dictionaries, MedicalDictionaries as Topic: Lists of words, usually in alphabetical order, giving information about form, pronunciation, etymology, grammar, and meaning.Aminoimidazole Carboxamide: An imidazole derivative which is a metabolite of the antineoplastic agents BIC and DIC. By itself, or as the ribonucleotide, it is used as a condensation agent in the preparation of nucleosides and nucleotides. Compounded with orotic acid, it is used to treat liver diseases.Peptide Synthases: Ligases that catalyze the joining of adjacent AMINO ACIDS by the formation of carbon-nitrogen bonds between their carboxylic acid groups and amine groups.Societies, Pharmaceutical: Societies whose membership is limited to pharmacists.Simbu virus: A species in the ORTHOBUNYAVIRUS genus of the family BUNYAVIRIDAE family. Previously a large group of serotypes, most are now considered separate species.Search Engine: Software used to locate data or information stored in machine-readable form locally or at a distance such as an INTERNET site.Methylurea Compounds: Urea compounds which are substituted with one or more methyl groups.Silk: A continuous protein fiber consisting primarily of FIBROINS. It is synthesized by a variety of INSECTS and ARACHNIDS.Spiders: Arthropods of the class ARACHNIDA, order Araneae. Except for mites and ticks, spiders constitute the largest order of arachnids, with approximately 37,000 species having been described. The majority of spiders are harmless, although some species can be regarded as moderately harmful since their bites can lead to quite severe local symptoms. (From Barnes, Invertebrate Zoology, 5th ed, p508; Smith, Insects and Other Arthropods of Medical Importance, 1973, pp424-430)Information Storage and Retrieval: Organized activities related to the storage, location, search, and retrieval of information.Phosphoribosylaminoimidazolecarboxamide Formyltransferase: An enzyme that catalyzes the conversion of aminoimidazole-4-carboxamide ribonucleotide to 5-formyl-aminoimidazole-4-carboxamide ribonucleotide in the purine de novo synthesis pathway. It requires the cofactor N(10)-FORMYLTETRAHYDROFOLATE as the formyl donor.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Expressed Sequence Tags: Partial cDNA (DNA, COMPLEMENTARY) sequences that are unique to the cDNAs from which they were derived.RNA-Binding Proteins: Proteins that bind to RNA molecules. Included here are RIBONUCLEOPROTEINS and other proteins whose function is to bind specifically to RNA.Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.RNA Splicing: The ultimate exclusion of nonsense sequences or intervening sequences (introns) before the final RNA transcript is sent to the cytoplasm.Planarians: Nonparasitic free-living flatworms of the class Turbellaria. The most common genera are Dugesia, formerly Planaria, which lives in water, and Bipalium, which lives on land. Geoplana occurs in South America and California.Stem Cells: Relatively undifferentiated cells that retain the ability to divide and proliferate throughout postnatal life to provide progenitor cells that can differentiate into specialized cells.Epidermis: The external, nonvascular layer of the skin. It is made up, from within outward, of five layers of EPITHELIUM: (1) basal layer (stratum basale epidermidis); (2) spinous layer (stratum spinosum epidermidis); (3) granular layer (stratum granulosum epidermidis); (4) clear layer (stratum lucidum epidermidis); and (5) horny layer (stratum corneum epidermidis).Cell Differentiation: Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.Turbellaria: A class of free-living freshwater flatworms of North America.Regeneration: The physiological renewal, repair, or replacement of tissue.Trichomonadida: An order of parasitic EUKARYOTES typically having four to six flagella. True cysts are known in very few species. Trichomonadida were formerly members of the class Zoomastigophora in the old five kingdom paradigm.Tritrichomonas foetus: A species of flagellate parasitic EUKARYOTE. It possesses a long undulating membrane that is bordered on its outer margin by a flagellum that becomes free posteriorly. This organism causes infections in cows that could lead to temporary infertility or abortion.Trichomonas vaginalis: A species of TRICHOMONAS that produces a refractory vaginal discharge in females, as well as bladder and urethral infections in males.Tritrichomonas: A genus of flagellate EUKARYOTES possessing three long anterior flagella.Amidophosphoribosyltransferase: An enzyme, involved in the early steps of purine nucleotide biosynthesis, that catalyzes the formation of 5-phosphoribosylamine from glutamine and phosphoribosylpyrophosphate. EC 2.4.2.14.Trichomonas: A genus of parasitic flagellate EUKARYOTES distinguished by the presence of four anterior flagella, an undulating membrane, and a trailing flagellum.