Pac-Man does not resolve the enduring problem of anaphase chromosome movement.

Protoplasma

School of Botany, University of Melbourne, Parkville, Victoria, 3052, Australia.

Published: February 2002

The Pac-Man hypothesis suggests that poleward movement of chromosomes during anaphase A is brought about by: disassembly of kinetochore microtubules (MTs) at the kinetochore; generation of the poleward force exclusively at or very close to the kinetochore; and the required energy coming from coupled disassembly of these MTs. This model has become widely accepted and cited as the sole or major mechanism of anaphase A. Rarely acknowledged are several significant phenomena that refute some or all of these postulates. We summarise these anomalies as follows: poleward movement of chromosomes occurring without insertion of any MTs at the kinetochore; "anaphase" shortening of kinetochore fibres in spindles entirely devoid of chromosomes and, presumably, kinetochores; continued movement of chromosomes while their severed kinetochore stub elongated poleward after treatment with UV microbeams; and fluxing of tubulin subunits through kinetochore MTs during anaphase A, indicating that during anaphase, kinetochore MTs disassemble partly or solely at the poles.

Download full-text PDF

Source
http://dx.doi.org/10.1007/BF01280300DOI Listing

Publication Analysis

Top Keywords

movement chromosomes
12
poleward movement
8
kinetochore
8
mts kinetochore
8
kinetochore mts
8
anaphase
5
mts
5
pac-man resolve
4
resolve enduring
4
enduring problem
4

Similar Publications

Maternal ELL3 loss-of-function leads to oocyte aneuploidy and early miscarriage.

Nat Struct Mol Biol

January 2025

Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, China.

Up to an estimated 10% of women experience miscarriage in their lifetimes. Embryonic aneuploidy is a leading cause for miscarriage, infertility and congenital defects. Here we identify variants of ELL3, a gene encoding a transcription elongation factor, in couples who experienced consecutive early miscarriages due to embryonic aneuploidy.

View Article and Find Full Text PDF

Background: Sturge-Weber Syndrome (SWS) is a rare, sporadic neurocutaneous disorder affecting the skin, brain, and eyes, due to somatic activating mutations in GNAQ or, less commonly, GNA11 gene. It is characterized by at least two of the following features: a facial capillary malformation, leptomeningeal vascular malformation, and ocular involvement. The spectrum of clinical manifestations includes headache, seizures, stroke-like events, intellectual disability, glaucoma, facial asymmetry, gingival hyperplasia, etc.

View Article and Find Full Text PDF

Blended phenotype of TECPR2-associated hereditary sensory-autonomic neuropathy and Temple syndrome.

Ann Clin Transl Neurol

January 2025

Department of Neurology, Movement Disorders Program, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA.

Uniparental isodisomy (UPiD) can cause mixed phenotypes of imprinting disorders and autosomal-recessive diseases. We present the case of a 3-year-old male with a blended phenotype of TECPR2-related hereditary sensory and autonomic neuropathy (HSAN9) and Temple syndrome (TS14) due to maternal UPiD of chromosome 14, which includes a loss-of-function founder variant in the TECPR2 gene [NM_014844.5: c.

View Article and Find Full Text PDF

Exercising regularly promotes health, but these benefits are complicated by acute inflammation induced by exercise. A potential source of inflammation is cell-free DNA (cfDNA), yet the cellular origins, molecular causes, and immune system interactions of exercise-induced cfDNA are unclear. To study these, 10 healthy individuals were randomized to a 12-wk exercise program of either high-intensity tactical training (HITT) or traditional moderate-intensity training (TRAD).

View Article and Find Full Text PDF

Opioid use disorder is heritable, yet its genetic etiology is largely unknown. C57BL/6J and C57BL/6NJ mouse substrains exhibit phenotypic diversity in the context of limited genetic diversity which together can facilitate genetic discovery. Here, we found C57BL/6NJ mice were less sensitive to oxycodone (OXY)-induced locomotor activation versus C57BL/6J mice in a conditioned place preference paradigm.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!