The Pre-Metaphase Stretch: A Re-Examination

Abstract

Pre-metaphase stretch is a term first coined by the preeminent cell biologist Sally Hughes-Schrader in 1950 to describe an elongation of prometaphase chromosomes observed in the primary spermatocytes of phasmid insects and praying mantids. Research from many groups since Hughes-Schrader’s initial observation has revealed reasons for both how and why chromosomes might elongate prior to metaphase. In this review, we describe Hughes-Schrader’s initial findings and discuss how recent work illuminates and provides some mechanistic explanation for this long-ago observed phenomenon.