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The eukaryotic initiation complex that synthesises an RNA primer and then a short DNA extension before handoff to more processive polymerases.
A eukaryotic replicative polymerase with a predominant leading-strand role during conventional nuclear replication.
Its synthesis is coordinated with the CMG helicase and accessory factors at the replication fork. A leading-strand preference describes the usual division of labour, while repair, altered forks and experimental perturbations can recruit different activities. [ref]
Molecular Biology of the Cell, 4th edition by Bruce Alberts and others. Chapter 5, DNA Replication Mechanisms
A eukaryotic replicative polymerase with a predominant lagging-strand role, also participating in initiation, strand displacement and repair contexts.
An E. coli polymerase participating in primer removal and gap filling, distinct from the principal chromosomal replicase DNA polymerase III.
The eukaryotic MSH2–MSH6 mismatch-recognition complex, acting on base mismatches and many small insertion–deletion loops.
The eukaryotic MSH2–MSH3 complex, with an important role in recognition of larger insertion–deletion loops.
An enzyme involved in methyl-directed DNA mismatch repair in E. coli. This mechanism should not be generalized to eukaryotic daughter-strand discrimination.
Its activity helps copy a CG methylation pattern after DNA replication. Reduced MET1 function can therefore change heritable chromatin states while leaving the corresponding DNA base order unchanged; this separates an epigenetic mark from a sequence mutation. [ref]
Molecular Biology of the Cell, 4th edition by Bruce Alberts and others. Chapters 4–7, chromatin, replication and gene regulation
Recognition of chromatin state helps couple DNA methylation to histone methylation, reinforcing a locally repressive environment. This is an interaction between two kinds of molecular mark, rather than conversion of one mark into the other. [ref]
Non-CG methylation patterns shape the epigenetic landscape in Arabidopsis by Hume Stroud and others. 2014, chromomethylases and non-CG methylation
This complements other plant methylation systems that act preferentially in different sequence or chromatin contexts. Separating CHH methylation from symmetric CG or CHG contexts is important because the patterns have different maintenance requirements after replication. [ref]
A methyltransferase recruited by RNA-directed DNA methylation that can establish methylation in multiple cytosine sequence contexts.
A plant DNA glycosylase/lyase involved in active DNA demethylation through a repair-associated pathway.
Active replacement can counterbalance methylation-dependent silencing at selected loci. This differs from passive dilution of a mark during replication, because the modified base is enzymatically removed through a repair-linked pathway. [ref]
ROS1, a repressor of transcriptional gene silencing in Arabidopsis, encodes a DNA glycosylase/lyase by Zhizhong Gong and others. 2002, glycosylase/lyase activity and silencing phenotype
A plant DNA glycosylase involved in reproductive epigenetic reprogramming and maternal imprinting effects.
Physical discontinuity of a chromosome. Fluorescent locus splitting or undercondensation can suggest vulnerability but needs additional evidence before being equated with a break.
Two distinct positive integers are amicable when the sum of the proper divisors of is and the sum of the proper divisors of is . The pair is an example. Iterating the proper-divisor sum can also produce longer directed cycles.
The perfection quotient of a positive integer is the ratio , where is the sum-of-divisors function. It distinguishes the three familiar classes: a deficient number has quotient below two, a perfect number has quotient two, and an abundant number has quotient above two. For example, the quotients of , and are , and .
For coprime integers , the quotient is multiplicative, since . At a prime power, its factor isConsequently a prescribed quotient can be studied one prime power at a time, tracking the remaining numerator and denominator.
A pair of positive integers with for a specified positive integer . Pairing each divisor with gives unordered factor pairs for nonsquare , and for a perfect square, where is the divisor function.
A divisor of a positive integer is unitary when . Each prime power in the prime factorization of must therefore be included in completely or omitted completely. Consequently, the sum of the -th powers of unitary divisors is .
Pinned article: Introduction to the OurBigBook Project
Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
Intro to OurBigBook
. Source. We have two killer features:
- topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculusArticles of different users are sorted by upvote within each article page. This feature is a bit like:
- a Wikipedia where each user can have their own version of each article
- a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
Figure 1. Screenshot of the "Derivative" topic page. View it live at: ourbigbook.com/go/topic/derivativeVideo 2. OurBigBook Web topics demo. Source. - local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
- to OurBigBook.com to get awesome multi-user features like topics and likes
- as HTML files to a static website, which you can host yourself for free on many external providers like GitHub Pages, and remain in full control
Figure 2. You can publish local OurBigBook lightweight markup files to either OurBigBook.com or as a static website.
Figure 3. Visual Studio Code extension installation.
Figure 5. . You can also edit articles on the Web editor without installing anything locally. Video 3. Edit locally and publish demo. Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension. 
- Infinitely deep tables of contents:
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact