Partial characterization of a major family of proteins in turions of Hydrilla verticillata

Electrophoretograms of turions of dioecious Hydrilla verticillata (L. f.) Royle, run under non-denaturing conditions, had a major complex protein band at R_f0.45 (7.5% acrylamide). Extracts of monoecious plants under similar conditions had major bands at R_f 0.43 and 0.45. The polypeptides which comprise these bands were partially purified and characterized. The major protein fraction in extracts of dioecious turions had a molecular mass of 58 kDa on gel permeation chromatography. Electrophoresis of this fraction under denaturing conditions in the presence of sodium dodecyl sulfate indicated principal bands with molecular masses of 58 and 57 kDa. Extracts from turions of the monoecious biotype had major bands at 59 and 55 kDa after electrophoresis under denaturing conditions. Antisera were raised against the proteins from the dioecious turion at R_f 0.45 after electrophoresis under non-denaturing conditions. When blots of gels run under non-denaturing conditions were probed with these antisera, a complex band was seen at R_f 0.45 for extracts of the dioecious biotype, while bands were observed at R_f 0.43 and 0.45 for the monoecious extracts. After electrophoresis under denaturing conditions, immunoreactive bands were noted at 58 and 57 kDa or 59 and 55 kDa in extracts of dioecious and monoecious turions, respectively. Extracts of leaves and stems of H. verticillata had detectable amounts of immunoreactive proteins, regardless of photoperiod, hence turion production. Related plants with the aquatic habit had immunoreactive proteins in their leaves and organs of perennation Elodea canadensis Michx., Elodea nuttallii (Planch.) St. John, and Egeria densa Planch., Potamogeton nodosus Poir. and P. pectinatus L.], but the presence of these proteins was not noted in other plants (Zea mays L., Allium cepa L., Spinacia oleracea L., Lemna gibba L., or Solanum tuberosum L.).