The Relationship between the Kinetics of Ribonucleic Acid Accumulation and the Morphological Development of the Fern Gametophyte, Dryopteris borreri

Analysis on the transcriptome information of two different wheat mutants and identification of salt-induced differential genes

This study established a wheat transcriptome library using RH8706-49 and RH8706-34. Salt-induced differential genes were screened by Illumina RNA sequencing (RNA-Seq). Five differential genes were chosen to study the functions by combining transcript sequencing result and gene chip. The expression changes of these five differential genes were analyzed using real-time quantitative PCR (qRT-PCR) technique to determine the reliability and accuracy of transcriptome sequencing and transplanted into Arabidopsis thaliana to obtain transgenic homozygote plants for the salt tolerance test. The salt tolerance test results show that the transgenic plants grew far better than the wild-type plant.

Protein crystalloids in ribosome-deficient plastids of Aeonium domesticum cv. variegatum (Crassulaceae)

Protein crystalloids are typical constituents of Aeonium domesticum plastids. They are composed of hexagonally arranged tube-like elements situated in the stroma without a bordering membrane. The single tubule has an external diameter of about 20 nm and an internal one of about 10 nm. The green-white-green mesochimera Ae. domesticum cv. variegatum contains normal chloroplasts in the green tissue and colourless plastids in the pale tissue. The defective plastids have a double-layered envelope, scarce internal membrane structures and contain, in the mature stage, a large vacuole. Plastid ribosomes can be detected only rarely in proplastids. They lose their ribosome complement entirely in the course of development. Polyacrylamide gel electrophoresis of total nucleic acids extracted from white tissue revealed the absence of the 23S and 16S rRNA normally present in plastids. Despite the loss of ribosomes, the plastids contain large protein crystalloids, which are structurally identical with those of normal green chloroplasts. Consequences concerning problems of encoding and transport of crystalloid protein(s) are briefly discussed.

Ribonucleic Acid Synthesis Associated with a Developmental Change in the Gametophyte of Pteridium aquilinum

When bacteria are subjected to step-down conditions, there is an enhanced production of a messenger-type of RNA for a short time after the shift. A cultural shift, which appears to be similar to step-down, is described for gametophytes of Pteridium aquilinum. When the cultures are grown in white light, a population of rapidly dividing cells is produced, whereas in red light cell elongation predominates. If the cultures growing in white light are shifted to red light, a transition occurs which involves a rapid decrease in growth and nucleic acid synthesis. In particular, there is a marked decline in RNA synthesis for a short time following the shift and prior to the initiation of the new mode of growth. It appears that this observed change in RNA synthesis is related to the initiation of the new mode of growth.