mis16 activity question

[ValWood]

mis16

this seems inconsistent

[ValWood]

Actually, this might be context dependent, I will dig in when time permits

Claude:

As a chaperone: Mis16 is a homologue of the human WD40-repeat protein RbAp46/48, a well-known histone chaperone found in a variety of chromatin-associated complexes. Its canonical function is binding histone H4. Life Science Alliance

Dual/switching role: Mis16 is a well-known ubiquitous histone H4 chaperone, but it also plays a centromere-specific role within the Mis18 holo-complex. Structurally, Mis16 accommodates Eic1 (or Mis19) through the binding pocket normally occupied by histone H4, indicating that Eic1/Mis19 and H4 compete for the same binding site — providing a mechanism for Mis16 to switch its binding partner from histone H4 to Eic1. PubMedPubMed

In the centromere context: In fission yeast, Scm3sp and the Mis18 complex (composed of Mis16, Eic1, and Mis18) function as a CENP-A(Cnp1)-specific chaperone and a recruiting factor, respectively, together ensuring accurate delivery of CENP-A(Cnp1) to centromeres.
So within the Mis18 complex, Mis16 acts more as a recruiting/assembly factor (adaptor-like) rather than a classical chaperone. ScienceDirect

In short: Mis16 is canonically a histone H4 chaperone, but when incorporated into the Mis18 holo-complex at centromeres, it functionally switches to behave more like an assembly/recruiting factor by exchanging its histone H4 interaction for Eic1/Mis19 binding.

[ValWood]

I still have an issue with the readers vs recruiters, need to sicuss with @PCarme at some point

https://www.pombase.org/term/GO:0140463