The family of CONSTANS-like genes in the moss Physcomitrella patens

The CONSTANS (CO) gene plays a central role in the regulation of flowering time in Arabidopsis, and is the founding member of a family of 17 CO homologues. CO and CO homologues have been found in flowering plants, but not in yeast and animals. To address the question of the origin of CO, this gene family was analysed in the moss Physcomitrella patens, a phylogenetically distant organism. In Arabidopsis and rice, three classes of CO homologues exist. The same three classes were found in Physcomitrella, suggesting that this gene family has ancient origins in the plant kingdom. In Arabidopsis, CO and 5 other genes belong to Group 1. Since only three Group 1 genes were identified in Physcomitrella, the family of CO homologues appears to be smaller in Physcomitrella than in Arabidopsis, in agreement with observations made with other gene families. Further analysis demonstrated that the Physcomitrella Group 1 genes are most similar to Arabidopsis Group 1 genes COL3/COL4/COL5, which are closely related to, but distinct from CO. An essential feature of CO function in Arabidopsis is a circadian controlled rhythm of transcript abundance. The three closely related Physcomitrella Group 1 genes have diurnal expression patterns that are distinct from the pattern of CO expression, and that are mainly caused by direct light induction. Distinct diurnal expression patterns are also observed for CO homologues that are not involved in control of flowering time. Consistently, the Physcomitrella CO homologues are unable to promote flowering upon expression in Arabidopsis. Together, the findings indicate that the CO branch of Group 1 genes does not exist in Physcomitrella. The role of CO in flowering time control was possibly derived from an ancestral function of Group 1 genes in light signal transduction. The function of the three Physcomitrella CO homologues was studied by exploiting the feasibility of gene targeting. A disruptant was generated for each Group 1 CO homologue in Physcomitrella, whereas in Arabidopsis only CO has been inactivated to date. Phenotypical analysis of the disruptants revealed no developmental defects, nor an alteration of the phototropic growth response. The high degree of sequence conservation between the three genes and the similar expression patterns suggest redundancy. Therefore, simultaneous inactivation of all three genes may be necessary to elucidate their function

Fertilizer Studies as Conducted on the Carbon County Experimental Farm with Special Reference to Treble-Superphosphate

In 1927 an experimental farm was established in Carbon County, Utah. The farm is on a new irrigation tract south of the Price River and about four miles south of Price. The agricultural problems of the Carbon County Experimental Farm and the locality which it serves are distinctly different from those of most of the farming sections in Utah. The soil of this region is of a sandy, silty nature apparently with deflocculated colloids which make it somewhat difficult to manage. There is a low percentage of organic matter in this soil, and because of this and its impervious condition the soil absorbs water slowly. The range in moisture content at which the soil may be tilled is rather narrow

An Accelerated Feeding Study for Dairy Beef Steers

A large number of Holstein bull (steer) calves are produced by the dairy industry. Producers who purchase these calves should understand that depending on the production strategy employed, the economic outcome could be quite broad. Dairy beef calves that are intensively managed, using aggressive feeding strategies to achieve high levels of efficiency, increase the opportunity for profitability

The effect of oxygen tension on the rate of oxidation of organic matter in sea water by bacteria

It is generally recognized that the oxygen consuming capacity of heterotrophic bacteria in water serves as a good criterion of the amount of respirable or oxidizable organic matter in the water. However, the fragmentary literature on the subject records contradictory observations on the effect of oxygen tension upon the rate of bacterial oxidations. For example, Pomeroy (1938) found the amount of oxygen consumed by diluted sewage containing from 0. 7 to 17 .5 cc. of oxygen per liter to be independent of the oxygen tension but Heukelekian (1936) noted the maximum consumption of oxygen in such sewage mixtures containing around 10.5 cc. of oxygen per liter...

Apparatus for collecting water samples from different depths for bacteriological analysis

Prerequisite to quantitative studies on the occurrence and importance of bacteria in the sea or other natural waters is a satisfactory device for collecting water samples for bacteriological analysis from any desired depth. Such a device must be easily sterilized, susceptible to aseptic manipulation under the most rigorous field conditions, possible to operate at high hydrostatic pressures and it must be made of biologically inert materials...

Measurement Invariance and Psychometric Properties of Career Indecision Profile-65 Scores: College Student and Non-College Samples

This thesis reports the results of a study conducted to examine psychometric properties of Career Indecision Profile-65 scores, including measurement invariance between college student and non-college samples. The responses of 529 college students and 472 non-college students to an online survey revealed that a four-factor structure fit the data in both samples well. Metric invariance was not supported. Six-week test-retest reliability was found to be high, and in the expected range. The tendency to maximize was found to be correlated strongly with one of the four factors. This study furthered the psychometric research for the Career Indecision Profile-65 and found evidence to support its use in practice and further research. Further implications, as well as limitations and future directions will be discussed

Studies on marine bacteria. I. The cultural requirements of heterotrophic aerobes

The observations of Issatchenko (1914), Benecke (1933), Waksman (1934), ZoBell (1938) and others have established that bacteria are quite widely distributed in the sea where they probably play an important role influencing chemical, physico-chemical, geological and biological processes. However, due primarily to the widely divergent analytical procedures which have been used by various investigators studying the distribution and activities of marine bacteria, the quantitative results obtained by different workers in different parts of the world are not comparable