Colocalization analysis of peripheral myelin protein-22 and lamin-B1 in the schwann cell nuclei of Wt and TrJ Mice

Di Tomaso, María Vittoria - Vázquez Alberdi, Lucía - Olsson, Daniela - Cancela Bruno, Saira - Fernández Constenla, Anabel Sonia - Rosillo Martí, Juan Carlos - Reyes Ábalos, Ana Laura - Álvarez Zabaleta, Magdalena - Calero, Miguel - Kun González, Alejandra E.

Resumen:

Myelination of the peripheral nervous system requires Schwann cells (SC) differentiation into the myelinating phenotype. The peripheral myelin protein-22 (PMP22) is an integral membrane glycoprotein, expressed in SC. It was initially described as a growth arrest-specific (gas3) gene product, up-regulated by serum starvation. PMP22 mutations were pathognomonic for human hereditary peripheral neuropathies, including the Charcot-Marie-Tooth disease (CMT). Trembler-J (TrJ) is a heterozygous mouse model carrying the same pmp22 point mutation as a CMT1E variant. Mutations in lamina genes have been related to a type of peripheral (CMT2B1) or central (autosomal dominant leukodystrophy) neuropathy. We explore the presence of PMP22 and Lamin B1 in Wt and TrJ SC nuclei of sciatic nerves and the colocalization of PMP22 concerning the silent heterochromatin (HC: DAPI-dark counterstaining), the transcriptionally active euchromatin (EC), and the nuclear lamina (H3K4m3 and Lamin B1 immunostaining, respectively). The results revealed that the number of TrJ SC nuclei in sciatic nerves was greater, and the SC volumes were smaller than those of Wt. The myelin protein PMP22 and Lamin B1 were detected in Wt and TrJ SC nuclei and predominantly in peripheral nuclear regions. The level of PMP22 was higher, and those of Lamin B1 lower in TrJ than in Wt mice. The level of PMP22 was higher, and those of Lamin B1 lower in TrJ than in Wt mice. PMP22 colocalized more with Lamin B1 and with the transcriptionally competent EC, than the silent HC with differences between Wt and TrJ genotypes. The results are discussed regarding the probable nuclear role of PMP22 and the relationship with TrJ neuropathy.


Detalles Bibliográficos
2022
ANII: FCE_1_2019_1_155539
PMP22
Lamin B1
Trembler-J
Schwann cells nuclei
Colocalization-analysis
Inglés
Universidad de la República
COLIBRI
https://hdl.handle.net/20.500.12008/38338
Acceso abierto
Licencia Creative Commons Atribución (CC - By 4.0)