Nuclear envelope attachment is not necessary for telomere function in fission yeast.
Inner nuclear membrane (INM) proteins can be important for positioning chromosomes within the nucleus. Little is known about INM proteins in the fission yeast Schizossacharomayces pombe. Telomeres are the most obvious chromosomal sites that are anchored to the nuclear envelope in this organism. A group of proteins that tether telomeres to the spindle-pole body (SPB) during meiotic prophase, such as Bqt1, Bqt2 and Sad1, has been identified previously, but proteins for anchoring telomeres to the nuclear envelope in vegetative cells have not been identified until recently. A recent report demonstrates that Bqt3 and Bqt4 are INM proteins that affect nuclear positioning of telomeres in vegetative cells, and consequently affect the telomere clustering in meiotic prophase. Interestingly, in the absence of Bqt4, telomeres are separated from the nuclear envelope but telomere silencing and telomere length are properly regulated. An important implication of these results is that the functional integrity of telomeres is maintained independently of their connection to the nuclear envelope.
Chikashige Y, Haraguchi T, Hiraoka Y