摘要:

AbstractSingle‐stranded DNA‐protein complex (T‐complex) is proposed to mediate T‐DNA transfer fromAgrobacteriumto plant cells. A novel model for transfer is presented which incorporates features of both bacterial conjugation and viral infection. Specific protein components of the T‐complex, its ultrastructure and possible functions in the plant cell are

ISSN:0265-9247    

DOI:10.1002/bies.950120302

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

摘要:

Abstractftzis one of the ‘pair rule’ segmentation genes ofDrosophila melanogaster, and is an important component of the segmentation process in the fruit fly. We discuss the transcriptional mechanism which causesftzto be expressed in a seven stripe pattern during embryogene

ISSN:0265-9247    

DOI:10.1002/bies.950120303

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

摘要:

AbstractClassical embryological studies have provided a great deal of information on the autonomy and stability of cell fate determination in early sea urchin embryos. However, these studies were limited by the tools available at the time, and the interpretation of the results of these experiments was limited by the lack of information available at the molecular level. Recent studies which have re‐examined classical experiments at the molecular level have provided important new insights into the mechanism of determination in sea urchins, and require us to re‐evaluate some long standing theories on the process of differentiat

ISSN:0265-9247    

DOI:10.1002/bies.950120304

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

摘要:

AbstractA protein kinase cascade is involved in the action of some mitogens. The cascade begins with receptor tyrosine kinase activation by growth factors. The resulting signal is transmitted into cellsviaphospholipid metabolism which produces a variety of second messengers and by intracellular protein kinase activation. The signal is then propagated and disseminatedviaa network of other proteln kinases and protein phosphatases. Recent research suggests that ribosomal protein S6 kinase and casein kinase II are two important elements in the kinase cascade that leads to the initiation of growth. The nature and some properties of these hitherto lesser known enzymes is considered.

ISSN:0265-9247    

DOI:10.1002/bies.950120305

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

摘要:

AbstractTransient changes in DNA torsional tension are generated by environmental stimuli and transcriptional activity. In eukaryotic cells, these changes can only be accommodated by a chromatin structure that is flexible. This property of chromatin may be essential to the regulation of eukaryotic gene activity.

ISSN:0265-9247    

DOI:10.1002/bies.950120306

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

ISSN:0265-9247    

DOI:10.1002/bies.950120307

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

ISSN:0265-9247    

DOI:10.1002/bies.950120308

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

ISSN:0265-9247    

DOI:10.1002/bies.950120309

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

摘要:

AbstractThe discovery of the signal peptides that direct proteins to localize at the nucleolus is described here. The nucleolar targeting signal termed the NOS consists of clustered basic amino acids organized such that a portion also functions as the nuclear transporting signal. Although a NOS has been identified within the regulatory genes of human retroviruses, HTLV‐I and HIV‐I, signals of similar function in cellular proteins – such as heat shock proteins – may be induced through the configurational change of protein structure by heat or

ISSN:0265-9247    

DOI:10.1002/bies.950120310

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

ISSN:0265-9247    

DOI:10.1002/bies.950120312

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY