Mutation of Arabidopsis SPLICEOSOMAL TIMEKEEPER LOCUS1 Causes Circadian Clock Defects

The circadian clock plays a crucial role in coordinating plant metabolic and physiological functions with predictable environmental variables, such as dusk and dawn, while also modulating responses to biotic and abiotic challenges. Much of the initial characterization of the circadian system has focused on transcriptional initiation, but it is now apparent that considerable regulation is exerted after this key regulatory step. Transcript processing, protein stability, and cofactor availability have all been reported to influence circadian rhythms in a variety of species. We used a genetic screen to identify a mutation within a putative RNA binding protein (SPLICEOSOMAL TIMEKEEPER LOCUS1 [STIPL1]) that induces a long circadian period phenotype under constant conditions. STIPL1 is a homolog of the spliceosomal proteins TFP11 (Homo sapiens) and Ntr1p (Saccharomyces cerevisiae) involved in spliceosome disassembly. Analysis of general and alternative splicing using a high-resolution RT-PCR system revealed that mutation of this protein causes less efficient splicing of most but not all of the introns analyzed. In particular, the altered accumulation of circadian-associated transcripts may contribute to the observed mutant phenotype. Interestingly, mutation of a close homolog of STIPL1, STIP-LIKE2, does not cause a circadian phenotype, which suggests divergence in function between these family members. Our work highlights the importance of posttranscriptional control within the clock mechanism. © 2012 American Society of Plant Biologists. All rights reserved

The world economy [February 1986]

The present recovery in the world economy has now proceeded for almost twice as long as the typical cyclical phase of expansion during the past four decades. Growth in 1985 and prospective growth for 1986 is, however, modest in comparison to both the rates achieved in earlier upswings and that of 1983-4 when world expansion was driven by the strong growth of the US economy. With the deceleration of the US economy from its phase of rapid expansion and the continuing policy caution in the countries of Western Europe and Japan, growth in the major industrialised economies is likely to be of the order of 2.5% in 1986

The Scottish economy [November 1984]

With the inauguration of the quarterly Scottish Business Survey (SBS) in September there are now two regular and up-to-date indicators of trends in the Scottish industrial sector. The combination of the new survey and the long-standing CBI Industrial Trends Survey provides a comprehensive and up to date assessment of trends in Scottish industry

Outlook and appraisal [February 1985]

During 1984 the British economy maintained the growth rate of 2.5% achieved in the latter part of 1983. Growth in 1984 was depressed by the coal dispute which meant the direct loss of mining income and output and an associated reduction in the overall demand for the output of sectors such as Metal Goods and Mechanical Engineering. Resolution of the miners' dispute in the early part of the year and a full return to work will, with the associated "rebound" in activity, lead to a growth rate for 1985 of around 3 The longer the dispute is prolonged, the closer UK growth to the end of 1985 will approach the underlying rate of about 2.

The Scottish economy [February 1985]

With the inauguration of the quarterly Scottish Business Survey (SBS) in September 1984 there are now two regular and up-to-date indicators of trends in the Scottish industrial sector. The combination of the new survey and the long-standing CBI Industrial Trends Survey provides a comprehensive assessment of trends in Scottish industry

The Scottish economy [May 1987]

With the Inauguration of the quarterly Scottish Business Survey (SBS) in October 1984 there are now two regular up-to-date indicators of trends in the Scottish industrial sector. The combination of the new survey and the long-standing CBI Industrial Trends Survey provides a comprehensive assessment of trends in Scottish industry. The two data sources are essentially complementary, but there are important differences between them

Outlook and appraisal [August 1987]

The outlook for the Scottish economy is favourable over the coming months, but probably less favourable than the outlook for the UK economy as a whole

Outlook and appraisal [May 1987]

The outlook for the Scottish economy is favourable over the coining months, but probably less favourable than the outlook for the UK economy as a whole

The Scottish economy [August 1984]

Throughout much of the last two years the official view has been that the Scottish recession was less severe than that experienced in the United Kingdom as a whole. Indeed, the Secretary of State has proclaimed to a variety of audiences, including the House of Commons, that Scotland was, and still is , leading the country out of recession. This diagnosis has not met with universal approval, as it appears to be founded primarily on the growth of the Scottish electronics sector and on the smaller proportionate rise in unemployment which has occurred in Scotland than in Britain as a whole. This latter fact is not particularly surprising as the pre-recession level of unemployment in Scotland was markedly above that of the rest of Britain

The Scottish economy [March 1988]

Since October 1984 there have been two regular surveys of Scottish businesses, one carried out by the Chambers of Commerce and the other by the CBI. These have the great advantage that they provide indications of the trends in a number of economic variables several months in advance of the publication of the official statistics . Moreover, they provide a basis for making assessments about the short-term prospects for the economy