The initiation zone may reflect a basal level of “random” initiation events bounded by two actively transcribed genes (4). Studies employing 2D-gel fractionation of total genomic DNA to detect replication bubbles or to map the polarity of replication forks generally conclude that initiation events are distributed uniformly over intergenic regions as large as 55 kb (“initiation zones”), whereas methods that map either the relative distribution or the relative abundance of nascent DNA strands along the genome invariably conclude that initiation events originate within specific loci of ~1 kb or less, similar in size to fission yeast origins ( Fig. We and others have mapped replication origins to specific genomic loci in differentiated cells of flies, frogs and mammals (1,2), but the nature of these loci, however, remains elusive. Origins in multicellular organisms generally lack ARS activity, although they do exhibit “replicator” activity (the ability to impart origin activity when translocated to other chromosomal sites), and they can be inactivated by sequence alterations. cerevisiae in terms of their size, sequence complexity, and their lack of a required consensus sequence. Thus, origins in multicellular eukaryotes are more similar to those in S. Origins in the fission yeast Schizosaccharomyces pombe lack a genetically required consensus sequence, although they do exhibit “autonomously replicating sequence” (ARS) activity. cerevisiae replication origins share only ~15% of their sequences in common a genetically required consensus sequence required for ORC binding (elements A & B1, Fig. For example, SV40 T-ag is assembled into a hexameric helicase only after binding to the SV40 replication origin. Viral origins contain a specific core DNA sequence that is required for initiation to proceed efficiently, whereas the requirement for specific DNA sequences is greatly diminished in single cell eukaryotes and virtually absent in multicellular eukaryotes. We and others have shown that they consist of binding sites for transcription factors that facilitate either binding of origin recognition proteins or DNA unwinding (3). Auxiliary origin components have been identified in both viral and cellular origins (e.g. The two leading strand initiation events that mark the OBR are separated by only one or two nucleotides (2). Most, if not all, eukaryotic origins initiate replication in both directions, resulting in a transition from discontinuous to continuous DNA synthesis on each template strand “origin of bi-directional replication” (OBR), Fig. DNA unwinding begins within the DUE, followed by DNA synthesis on each of the resulting single-stranded DNA templates. ORC), and an easily unwound sequence “DNA unwinding element” (DUE). We and others have shown that they consist of two essential components (1) : one or more binding sites for an origin recognition protein (e.g. There is no official support for Windows builds.Site-specific DNA replication origins exist in all prokaryotes, their plasmids and their phage, as well as in animal and plant viruses, and all single cell eukaryotes studied to date. Redis may work in Solaris-derived systems like SmartOS, but support is best effort. Linux and OS X are the two operating systems where Redis is developed and tested the most, and we recommend using Linux for deployment. *BSD, and Mac OS X, without external dependencies. Redis is written in ANSI C and works on most POSIX systems like Linux, You can use Redis from most programming languages. Redis supports asynchronous replication, with fast non-blocking synchronization and auto-reconnection with partial resynchronization on net split. You can also disable persistence if you just need a feature-rich, networked, in-memory cache. Or by appending each command to a disk-based log. Depending on your use case, Redis can persist your data eitherīy periodically dumping the dataset to disk To achieve top performance, Redis works with an Or getting the member with highest ranking in a sorted set. Incrementing the value in a hash pushing an element to a On these types, like appending to a string Redis has built-in replication, Lua scripting, LRU eviction, transactions, and different levels of on-disk persistence, and provides high availability via Redis Sentinel and automatic partitioning with Redis Cluster. Strings, hashes, lists, sets, sorted sets with range queries, bitmaps, hyperloglogs, geospatial indexes, and streams. Redis is an open source (BSD licensed), in-memory data structure store used as a database, cache, message broker, and streaming engine. Learn about the Redis open source project
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