Brain Chromosome

Unstained brain chromosomes can be prepared according to the same experimental regimes described above for aceto-orcein squashes. The procedure for this type of preparation is given in Protocol 1.2. 

The gene for myophosphoiylase has been assigned to chromosome 1 lql3. The enzyme is a dimer of two identical 97 IcDa subunits and is the sole isoform present in skeletal muscle. Heart and brain also contain this isoform in addition to a distinct brain isoenzyme and a hybrid muscle/brain isoform. Smooth muscle also contains a phosphorylase isoform distinct from the muscle isoenzyme. If regenerating muscle fibers are present they also contain phosphorylase activity due to the presence, in fetal and developing muscle, of an isoform said to be identical with brain phosphorylase. 

White, D. M., et al. (1992). Structure and chromosomal localization of the human gene for a brain form of prostaglandin D2 synthase. J. Biol. Chem. 267,... 

Curiously, functions proposed for some brain KRPs [55] are very different from functions proposed for similar or identical KRPs in no-neuronal cells. For example, members of the kinesin-13 family have been implicated in both mitotic spindle function and in axonal membrane transport. Similarly, a mouse kinesin-4 was reported to associate with unidentified MBOs in neurites, but its chicken homolog bound to chromosomal DNA and mediates chromosome movements in the mitotic spindle. Finally, a kinesin-6 was originally found to have a role in mitotic spindle function, but members of the kinesin-6 family were also implicated in the transport of MTs into dendrites [56]. 

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