Mutation within the conserved region of a 5.8kb HindIII Cdk1 genomic fragment (amino acid replacement A171T), mutation corresponds to a known temperature sensitive allele of S. pombe cdc2.
Nuclear pore complexes and annulate lamellae pore complexes (ALPCs) do not disassemble at 30oC in cdc2A171T embryos, but the pore complexes disassemble and reassemble normally in cdc2A171T embryos at 22oC. The quantity of ALPCs in cdc2A171T embryos at 30oC is substantially higher than in wild-type embryos at 30oC or in cdc2A171T embryos at 22oC.
cdc2A171T wing discs are typically smaller in size than wild-type and have fewer cells that are bigger than normal. The observed aberrant centriole pairs found in cdc2A171T mutant wing discs are attributable to excess growth of the daughter cell compared to wild-type (63% increase compared to wild-type). One of the observed aberrant centriole morphologies of cdc2A171T mutants consists of centriole pairs in which the daughter centriole is longer than the mother. About 12.5% of centrioles in cdc2A171T wing discs are triplets containing three centrioles in one of two different configurations, neither of which is observed in wild-type. In cdc2A171T mutants, movement of the daughter centriole away from the mother is not necessary to initiate assembly of a new second-generation daughter (grand-daughter).
Duplication of muscle DA1 can be seen in embryos carrying four copies of cdc2A171T (in a cdc2B47 background) which have been shifted to the non-permissive temperature. RP2 neuron duplication and large RP2 neurons are seen in 42.7% and 4.6% of cases respectively. Temperature upshifts can also result in the arrest of neuroblasts in G2 in these embryos.
The polar bodies decondense in embryos raised at the restrictive temperature. Chromosomes decondense and become surrounded by the nuclear envelope in embryos after inactivation of cdc2A171T at 30oC for 15 minutes.
fzy- embryos carrying P{Dmcdc2A171T} at 18oC exhibit mitotic arrest at stage 11 in the ventral region, as expected. Temperature shift to the restrictive temperature causes a drastic reduction in the number of metaphase arrested cells.
Meiotic spindles and metaphase plates are never formed at high temperatures. Chromosomes still condense in late spermatocytes and spermatid differentiation continues.
Construct has no activity at high temperatures (29oC), rescue is best at 18oC.