Fraction 1 protein and the origin of the European potato

The origin of the cultivated tetraploid potato based on chloroplast DNA

By using restriction enzyme analysis of chloroplast DNA, a geographical cline from the Andean region to coastal Chile was found for the tetraploid potato (Solanum tuberosum). This supports the Andean origin of Chilean ssp. tuberosum. One of the relic cultivars of the early introduction of potato to Europe had ssp. andigena type chloroplast DNA. Its derivatives were largely lost in the mid-19th century due to the late blight epidemic and were replaced by ssp. tuberosum originally introduced from Chile. Therefore, the present common potato has the same type chloroplast DNA as Chilean ssp. tuberosum.

Who is the mother of the potato? - restriction endonuclease analysis of chloroplast DNA of cultivated potatoes

Chloroplast DNA from 44 lines of 16 wild and 7 cultivatedSolanum species were compared by restriction endonuclease analysis. Seven chloroplast genome types were identified among them by 5 restriction enzymes: Type A (S. tuberosum ssp.andigena andS. maglia); Type S (S. goniocalyx, S. phureja, S. stenotomum, S. ×chaucha and a line of ssp.andigena); Type C (S. acaule, S. bukasovii, S. canasense, S. multidissectum andS. ×juzepczukii); Type T (S. tuberosum ssp.tuberosum); Type W (other wild species); Type W' (S. chacoense f.gibberulosum) and Type W″ (S. tarijense). From this cytoplasmic identification, it was concluded thatS. goniocalyx, S. phureja, S. ×chaucha and ssp.andigena were derived fromS. stenotomum or its primitive type, which may have originally evolved itself fromS. canasense. The chloroplast genome of the European potato, however, was introduced from the Chilean potato, which might have been primarily constructed with the nuclear genome from ssp.andigena and with cytoplasm from other species. The cytoplasmic donor of the Chilean potato could not be determined.

Chloroplast DNA variation between the common cultivated potato (Solanum tuberosum ssp. tuberosum) and several South American relatives

Chloroplast DNA (ctDNA) from the tuberbearing Solanum species tuberosum, vernei, phureja, and chacoense has been compared by restriction endonuclease analysis. Digestion by Hind III or Xba I reveal no differences, but digestion with Bam HI and Eco RI reveals minor differences in the ctDNA among these species. The ctDNA restriction patterns of the tetraploid common cultivated potato of North America and Europe, S. tuberosum ssp. tuberosum and the South American tetraploid, S. tuberosum ssp. andigena are identical for all four restriction endonucleases. These data suggest that ssp. tuberosum and ssp. andigena contain similar ctDNA and therefore may share a common ancestor, or direct lineage. The ctDNA restriction patterns of S. vernei and S. chacoense are identical for all four restriction endonucleases, and S. phureja ctDNA, can be distinguished from the other diploid ctDNAs by digestion with Bam HI. None of the diploids analyzed contain ctDNA identical to the tetraploids and therefore either did not contribute their chloroplast genomes to the evolution of the tetraploids, or the ctDNA has diverged since this evolutionary event. The ctDNAs studied did not contain restriction polymorphisms which could be correlated to cytoplasmic male sterility in Solanum. This is the first demonstration of ctDNA diversity in the tuber-bearing Solanum species.

Heterogeneity of alkaline small subunits of ribulose 1,5 bisphosphate carboxylase-oxygenase from Medicago sativa and M. falcata

The isolated leaf proteins of lucerne (Medicago sativa L. and M. falcata L.) were fractionated by Sepharose 6B column chromatography. Analysis of fractionated proteins indicated that the 2nd peak component was almost entirely ribulose 1,5 bisphosphate carboxylase-oxygenase (Rubisco) which represented 57% of the total recovered protein.Rubisco yielded one large subunit (LSU) and one small subunit (SSU) polypeptide after SDS gel electrophoresis.Isoelectric focusing of the SSU of Rubisco from genotypes of M. sativa cv. Hunter River (HR), Hairy Peruvian (HP) and of M. falcata (MF) showed two SSU components for HR and HP, and three components for MF. Most components of genotypes were located in the alkaline region of the gel. While the pIs of the SSU components of HR and HP were identical they differed from those of the SSU of MF thus demonstrating heterogeneity for SSU in Medicago.It is suggested that the alkaline nature of SSU may have some adaptive physiological significance.

Two dimensional analysis of chloroplast proteins from normal and cytoplasmic male sterile Brassica napus

Stromal and thylakoid proteins isolated from normal (N) and cytoplasmic male sterile (cms) lines of Brassica napus have been compared using a two dimensional gel separation. It has been shown that: 1) stromal compartments of the two lines were very similar; 2) although there was extensive homology between protein maps of thylakoids isolated from the two lines, these could be distinguished by the spots corresponding to the β subunits of the coupling factor CF1 from the ATPase complex.