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PubMed · 806651

Conjugation in Oxytricha bifaria: cell interaction.

N Ricci·F Esposito·R Nobili
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Abstract

As a model of cell interaction, the mating process of Oxytricha bifaria has been investigated. Mating involves several distinct and sterotyped stages, each lasting a determined time, and ending with the formation of firmly united pairs. A "waiting period" intervenes between the mixture of complimentary mating types and the onset of cell interaction. A proper starvation shortens the waiting period (25 min vs 120 min). Treatment of properly starved cells with heterologous cell-free fluid further reduces the waiting period. Certain enzyme treatments (pronase, trypsin and lipase) dramatically increase the waiting period in both washed enzyme-treated cells and in unwashed cells. Trypsin inhibits the first two stages of the mating process, while lipase inhibits membrane fusion between mates.

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Cell DivisionCiliophoraCulture MediaLipasePhospholipasesPronaseTime FactorsTrypsinJournal Article

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N Ricci, F Esposito, R Nobili. 1975. Conjugation in Oxytricha bifaria: cell interaction.. https://doi.org/10.1002/jez.1401920307

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