The misaligned undulating membrane (mum) mutant of @entity14825 is a non-conditional, single gene recessive mutation. The major effect of the mum mutation is the production of multiple undulating membrane (UM) fragments in the @entity1697 ( @entity1697 ). The ultrastructure of the UM fragments of mum @entity29624 is identical to that of the single UM of wild-type @entity29624 . Analysis of @entity1697 development at midbody using a combination of light microscopy of protargol-stained cells and SEM of demembranated whole cells showed that the phenotypic effect of the mum mutation first becomes evident during mid to late stage 4 and is fully manifested in early stage 5. The effect of the mutation involves a proliferation of excess basal bodies in the UM field. Subsequent events in the development of the mum @entity1697 from mid to late stage 5 are identical to those in wild-type @entity29624 . This study suggests that the mum mutation establishes conditions that allow the production of multiple UMs and thus reveals that the UM field is competent for the complete and coordinated development of several adjacent UMs. This level of regional control is not clearly evident when a single UM is present. The comparison of development of wild-type and mum @entity29624 required an extensive reanalysis of stages 4 and 5 of normal oral development. On the basis of current and previous observations, we propose a new and more subdivided staging system for oral development in @entity14825 .

Oral ultrastructure and oral development of the misaligned undulating membrane mutant of XXXX .

@entity29624 :: ('MESH:C537043', 'Disease') :: ['OAs'] @entity14825 :: ('5911', 'Species') :: ['Tetrahymena', 'Tetrahymena thermophila'] @entity1697 :: ('MESH:D009062', 'Disease') :: ['oral apparatus', 'OA']
@entity14825 :: (5911,Species) :: ['Tetrahymena thermophila']
