High light stimulates Deg1-dependent cleavage of the minor LHCII antenna proteins CP26 and CP29 and the PsbS protein in Arabidopsis thaliana.

The chloroplast Deg1 protein performs proteolytic cleavage of the photodamaged D1 protein of the photosystem II (PSII) reaction center, PSII extrinsic subunit PsbO and the soluble electron carrier plastocyanin. Using biochemical, immunological and mass spectrometry approaches we showed that the heterogeneously expressed Deg1 protease from Arabidopsis thaliana can be responsible for the degradation of the monomeric light-harvesting complex antenna subunits of PSII (LHCII), CP26 and CP29, as well as PSII-associated PsbS (CP22/NPQ4) protein. The results may indicate that cytochrome b (6) protein and two previously unknown thylakoid proteins, Ptac16 and an 18.

[The results of cytogenetic investigations in 107 couples with recurrent spontaneous abortions from Pomerania-Kujawy region of Poland].

About 10-15% of clinically diagnosed pregnancies end by spontaneous abortion. One of the causes of recurrent abortions is the presence of chromosome aberrations in a parent. The paper presents the results of cytogenetic investigations in 107 couples referred to genetic council clinic because of at least 2 spontaneous abortions.