A WIDESPREAD B CHROMOSOME POLYMORPHISM MAINTAINED WITHOUT APPARENT DRIVE

B Chromosomes – A Matter of Chromosome Drive

B chromosomes are supernumerary chromosomes which are often preferentially inherited, deviating from usual Mendelian segregation. The balance between the so-called chromosome drive and the negative effects that the presence of Bs applies on the fitness of their host determines the frequency of Bs in a particular population. Drive is the key for understanding most B chromosomes. Drive occurs in ...

Rapid suppression of drive for a parasitic B chromosome.

The persistence of parasitic B chromosomes in natural populations depends on both B ability to drive and host response to counteracting it. In the grasshopper Eyprepocnemis plorans, the B24 chromosome is the most widespread B chromosome variant in the Torrox area (Málaga, Spain). Its evolutionary success, replacing its ancestral neutralized B variant, B2, was based on meiotic drive in females, ...

Nondisjunction in favor of a chromosome: the mechanism of rye B chromosome drive during pollen mitosis.

B chromosomes (Bs) are supernumerary components of the genome and do not confer any advantages on the organisms that harbor them. The maintenance of Bs in natural populations is possible by their transmission at higher than Mendelian frequencies. Although drive is the key for understanding B chromosomes, the mechanism is largely unknown. We provide direct insights into the cellular mechanism of...

Sex Chromosome Meiotic Drive

X chromosome drive

How are toxic proteins cleared by microglia? Since microglia are the macrophages of the CNS, the promotion of an increase in their ability to phagocytose highly toxic proteins is a promising new therapeutic approach to prevent many diseases. Toxic proteins are produced in a variety of brain diseases, such as Alzheimer’s disease (b-amyloid), amyotrophic lateral sclerosis (superoxide dismutase 1)...