Abstract
BackgroundMidsegment duplication (dup) of chromatid arms may be symmetric or asymmetric. It can be argued that every dup should yield a discommensured RC with (a) loss of at least one duplicated unit to the template counterpart and; (b) deletion of all sections of the replicating chromatid arm that are distal to both the gap left by the duplicating process and the segment closest to the centromere.HypothesisMechanisms capable of recommensuring the stack of chromatids after topological shifts of duplicated units (dups) are discussed. The mechanics might fail in few cases, which are discussed in terms of statistics and scalability.ConclusionThe dynamics of the highly non-linear processes discussed here may be relevant to duplications of smaller (epsilon) subunits such as telomeric units within malignant genomes.
Highlights
Midsegment duplication of chromatid arms may be symmetric or asymmetric
The dynamics of the highly non-linear processes discussed here may be relevant to duplications of smaller subunits such as telomeric units within malignant genomes
Generalizing, every dup should invariably yield a discommensured replication of sister chromatids (RC) with two concomitant defects: (a) loss to the template counterparts (TC) of one duplicated unit; (b) deletion of all RC arm sections that are distal to both the gap and the segment closest to the centromere
Summary
Midsegment duplication (dup) of chromatid arms has been discussed in [1]. Alternative formats of the process yield duplicated units (dups) that are either "direct", i.e. stacked congruently in the chromatid, or "indirect", i.e. stacked upside down along the arm of the hosting chromatid. Generalizing, every dup should invariably yield a discommensured RC with two concomitant defects: (a) loss to the TC of one (or more) duplicated unit; (b) deletion of all RC arm sections that are distal to both the gap and the segment closest to the centromere. These segments are initially separated by the gap left when dup 5 is incorporated by the TC Such configurations occur at prophase when the still-intact nuclear envelope allows "last minute" repair of chromatid defects before its breakdown limits rectification of chromosomes traveling to equatorial congression. The loop distorts the TC so that its stack is not optimally streamlined to minimize viscous drag during equatorial congression through the spindle's fibrogel To reduce such drag, S2 must be rewound and restacked coaxially, as in panel (3). Indirect or upside-down duplications are less probable than the direct variants
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
