Multiple Layers of Regulation on Leaf Senescence: New Advances and Perspectives

Leaf senescence is the last stage of leaf development and is an orderly biological process accompanied by degradation of macromolecules and nutrient recycling, which contributes to plant fitness. Forward genetic mutant screening and reverse genetic studies of senescence-associated genes (SAGs) have revealed that leaf senescence is a genetically regulated process, and the initiation and progression of leaf senescence are influenced by an array of internal and external factors. Recently, multi-omics techniques have revealed that leaf senescence is subjected to multiple layers of regulation, including chromatin, transcriptional and post-transcriptional, as well as translational and post-translational levels. Although impressive progress has been made in plant senescence research, especially the identification and functional analysis of a large number of SAGs in crop plants, we still have not unraveled the mystery of plant senescence, and there are some urgent scientific questions in this field, such as when plant senescence is initiated and how senescence signals are transmitted. This paper reviews recent advances in the multiple layers of regulation on leaf senescence, especially in post-transcriptional regulation such as alternative splicing.

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The melanocortin system

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00434.2002 ◽

2003 ◽

Vol 284 (3) ◽

pp. E468-E474 ◽

Cited By ~ 264

Author(s):

Ira Gantz ◽

Tung M. Fong

Keyword(s):

Sexual Function ◽

Energy Homeostasis ◽

Melanocortin Receptors ◽

Experimental Basis ◽

Melanocortin System ◽

Genetic Studies ◽

Melanocortin Peptides ◽

Selective Agonists ◽

Made In

The melanocortin system consists of melanocortin peptides derived from the proopiomelanocortin gene, five melanocortin receptors, two endogenous antagonists, and two ancillary proteins. This review provides an abbreviated account of the basic biochemistry, pharmacology, and physiology of the melanocortin system and highlights progress made in four areas. In particular, recent pharmacological and genetic studies have affirmed the role of melanocortins in pigmentation, inflammation, energy homeostasis, and sexual function. Development of selective agonists and antagonists is expected to further facilitate the investigation of these complex physiological functions and provide an experimental basis for new pharmacotherapies.

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An Analysis of Systems of Classifying Mild Cognitive Impairment in Older People

Australian & New Zealand Journal of Psychiatry ◽

10.1046/j.1440-1614.2002.00972.x ◽

2002 ◽

Vol 36 (1) ◽

pp. 133-140 ◽

Cited By ~ 37

Author(s):

Alexander Collie ◽

Paul Maruff

Keyword(s):

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Older People ◽

Classification Systems ◽

Inclusion Criteria ◽

Exclusion Criteria ◽

Genetic Studies ◽

The Past ◽

Made In

Objective: Over the past two decades, a number of systems have been developed for the classification of cognitive and behavioural abnormalities in older people, in order that individuals at high risk of developing neurodegenerative disease, particularly Alzheimer's disease, may be identified well before the disease manifests clinically. This article critically examines the inclusion and exclusion criteria of a number of such classification systems, to determine the effect that variations in criterion may have on clinical, behavioural and neuroimaging outcomes reported from older people with mild cognitive impairment. Method: Qualitative review of the literature describing systems of classifying mild cognitive impairment, and outcomes from clinical, behavioural, neuroimaging and genetic studies of older people with mild cognitive impairment. Results: The exclusion and inclusion criteria for these classification systems vary markedly, as do the design of studies upon which the validity of these systems has been assessed. Minor changes to individual exclusion/inclusion criterion may result in substantial changes to estimates of the prevalence and clinical outcome of mild cognitive impairment, while inadequate experimental design may act to confound the interpretation of results. Conclusions: As a result of these factors, accurate and consistent estimates of the outcome of mild cognitive impairments in otherwise healthy older people are yet to be obtained. On the basis of this analysis of the literature, optimal criteria via which accurate classifications of mild cognitive impairment can be made in future are proposed.

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Description of an Operating Closed Cycle: Helium Gas Turbine

ASME 1963 Aviation and Space, Hydraulic, and Gas Turbine Conference and Products Show ◽

10.1115/63-ahgt-74 ◽

1963 ◽

Cited By ~ 1

Author(s):

James K. La Fleur

Keyword(s):

Gas Turbine ◽

Working Fluid ◽

Refrigeration Cycle ◽

Preliminary Design ◽

Closed Cycle ◽

Helium Gas ◽

Compressor Inlet ◽

Last Stage ◽

Low Temperature Refrigeration ◽

Made In

In May of 1960 La Fleur Enterprises, later to become The La Fleur Corporation, undertook the design of a closed-cycle gas turbine utilizing helium as a working fluid. The useful output of this machine was to be in the form of a stream of helium bled from the last stage of the compressor. This stream was to be used in a low-temperature refrigeration cycle (not described in this paper) and would be returned to the compressor inlet at approximately ambient temperature and at compressor-inlet pressure. The design of this machine was completed by the end of 1960 and construction was initiated immediately. The unit was completed and initial tests were made in the Spring of 1962. This paper covers the design philosophy as it affected the conceptual and preliminary design phases of the project and describes briefly the design of the various components. Photographs of these components and a flow schematic are included.

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Construction of the Leaf Senescence Database and Functional Assessment of Senescence-Associated Genes

Methods in Molecular Biology - Plant Genomics Databases ◽

10.1007/978-1-4939-6658-5_19 ◽

2016 ◽

pp. 315-333 ◽

Cited By ~ 9

Author(s):

Zhonghai Li ◽

Yi Zhao ◽

Xiaochuan Liu ◽

Zhiqiang Jiang ◽

Jinying Peng ◽

...

Keyword(s):

Leaf Senescence ◽

Functional Assessment ◽

Senescence Associated Genes

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Options and Choices in Relation to Adopting Healthy Lifestyles in the Pacific Islands Region

Journal of Developing Societies ◽

10.1177/0169796x19826733 ◽

2019 ◽

Vol 35 (1) ◽

pp. 62-82

Author(s):

Roy Smith

Keyword(s):

Pacific Islands ◽

Healthy Lifestyle ◽

Marshall Islands ◽

Health Transition ◽

The Pacific ◽

Significant Burden ◽

The Republic ◽

Internal And External Factors ◽

Lifestyle Related Diseases ◽

Made In

The low-lying atoll states of the Pacific region, including Kiribati, Tuvalu, and the Republic of the Marshall Islands, face numerous challenges as a result of climate change and the related rise in sea level. A health transition from communicable to noncommunicable lifestyle-related diseases among these communities is placing a significant burden on medical services and broader welfare provision. This article considers the broad range of both internal and external factors that influence the options available and choices made in relation to being able to maintain a healthy lifestyle in these communities.

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Conjoined Twins — A Genealogical Study

Acta geneticae medicae et gemellologiae ◽

10.1017/s1120962300025488 ◽

1970 ◽

Vol 19 (1-2) ◽

pp. 213-216 ◽

Cited By ~ 1

Author(s):

George B. Callahan ◽

Roy C. Mitchell

Keyword(s):

North Carolina ◽

Medical Schools ◽

Conjoined Twins ◽

The State ◽

Family Tree ◽

Genetic Studies ◽

Court Records ◽

Siamese Twins ◽

Image Position ◽

Made In

Beautiful and brilliant, content and capable, skillful and successful, these and multiple other adjectives may be used to describe persons on a family tree of Eng-Chang, the original Siamese twins (Fig. 1). These men chose the State of North Carolina for homes, and are considered among its most renowned citizens. They had some of the above characteristics and their descendants shared others.Data upon six generations of Eng-Chang families — some verified by their 1836 pamphlets, others as recent as 1969 court records in their county residence — are shown in the following table:Fig. 2 shows second and third generations in family groups made in the summer of 1865. Nine of Eng's 11 children are shown; 2 had died young. Likewise, 9 of Chang's 10 children are seen; one was born in 1868, as certified by Edinburgh's famous Prof. James Y. Simpson (1869). Two sets of twins, not joined, are recorded in their descendants. Though some members on this family tree are difficult to certify, the data available in these six generations are by far the most comprehensive found. Chromosome and other genetic studies are being initiated and pursued in anatomy departments of American and Thai Medical Schools.

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INHERITANCE OF BUNT AND LOOSE SMUT REACTION AND OF CERTAIN OTHER CHARACTERS IN KOTA × RED BOBS AND GARNET CROSSES

Canadian Journal of Research ◽

10.1139/cjr33-016 ◽

1933 ◽

Vol 8 (2) ◽

pp. 147-172 ◽

Cited By ~ 1

Author(s):

Thomas Kilduff

Keyword(s):

Pure Line ◽

Loose Smut ◽

Linkage Groups ◽

Genetic Studies ◽

Resistance Factors ◽

Kernel Color ◽

Resistant Varieties ◽

Susceptibility Factors ◽

The Difference ◽

Made In

Genetic studies were made in F2, F3 and F4 on the progeny of two common wheat crosses, Kota × Red Bobs and Kota × Garnet. Two chlamydospore collections from pure line hosts were used for inoculation in the bunt studies. The heritable nature of bunt reaction was clearly demonstrated in these crosses and evidence obtained that the degree of resistance found in Garnet must be conditioned by a single major factor. No genie hypothesis could be offered to explain the findings in regard to loose smut reaction due to a lack of agreement in infection percentages in the F3 and F4. Red kernel color in Kota and Red Bobs was found to be governed by two factor pairs. The results on the inheritance of awn characters agreed with the earlier findings of Clark and other workers with crosses of similar awned types, several factor pairs being involved. Two main factors appeared to condition the difference in strength of straw between Kota and Garnet, but the entire expression of the character can best be explained on a multiple factor basis. Correlated inheritance studies, made with the use of the correlation ratio η, indicated the presence of two linkage groups concerned with reaction to the bunt forms used. However, the linkage apparent between strength of straw and bunt susceptibility factors and between awn type and bunt resistance factors is not considered to be close enough to interfere with breeding for desirable bunt resistant varieties.

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Abiotic Stresses Intervene with ABA Signaling to Induce Destructive Metabolic Pathways Leading to Death: Premature Leaf Senescence in Plants

International Journal of Molecular Sciences ◽

10.3390/ijms20020256 ◽

2019 ◽

Vol 20 (2) ◽

pp. 256 ◽

Cited By ~ 20

Author(s):

Muhammad Asad ◽

Shamsu Zakari ◽

Qian Zhao ◽

Lujian Zhou ◽

Yu Ye ◽

...

Keyword(s):

Leaf Senescence ◽

Abiotic Stresses ◽

Inhibitory Effect ◽

Signal Molecules ◽

Aba Signaling ◽

Endogenous Factors ◽

Premature Leaf Senescence ◽

Signaling Receptors ◽

Future Outcomes ◽

Senescence Associated Genes

Abiotic stresses trigger premature leaf senescence by affecting some endogenous factors, which is an important limitation for plant growth and grain yield. Among these endogenous factors that regulate leaf senescence, abscisic acid (ABA) works as a link between the oxidase damage of cellular structure and signal molecules responding to abiotic stress during leaf senescence. Considering the importance of ABA, we collect the latest findings related to ABA biosynthesis, ABA signaling, and its inhibitory effect on chloroplast structure destruction, chlorophyll (Chl) degradation, and photosynthesis reduction. Post-translational changes in leaf senescence end with the exhaustion of nutrients, yellowing of leaves, and death of senescent tissues. In this article, we review the literature on the ABA-inducing leaf senescence mechanism in rice and Arabidopsis starting from ABA synthesis, transport, signaling receptors, and catabolism. We also predict the future outcomes of investigations related to other plants. Before changes in translation occur, ABA signaling that mediates the expression of NYC, bZIP, and WRKY transcription factors (TFs) has been investigated to explain the inducing effect on senescence-associated genes. Various factors related to calcium signaling, reactive oxygen species (ROS) production, and protein degradation are elaborated, and research gaps and potential prospects are presented. Examples of gene mutation conferring the delay or induction of leaf senescence are also described, and they may be helpful in understanding the inhibitory effect of abiotic stresses and effective measures to tolerate, minimize, or resist their inducing effect on leaf senescence.

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Chato Murciano pig breed: genetic and ethnozoological characterization

Animal Genetic Resources Information ◽

10.1017/s1014233900002078 ◽

2006 ◽

Vol 38 ◽

pp. 77-86 ◽

Cited By ~ 1

Author(s):

B. Peinado ◽

J.L. Vega-Pla ◽

M.A. Martínez ◽

M. Galián ◽

C. Barba ◽

...

Keyword(s):

Morphological Characterization ◽

Data Sets ◽

Large White ◽

Data Set ◽

Genetic Studies ◽

Original Population ◽

Accuracy And Precision ◽

Qualitative Variables ◽

Made In

SummaryThe Chato Murciano is the only surviving breed of pig of those historically farmed in the region of Murcia for their quality meat. At present, it is on the verge of extinction, having a population of only 260 reproductive animals. This paper describes the genetic studies made in the conservation and recovery programme of this breed of pig. A study of the morphological characterization of these animals was carried out first, measuring thirteen quantitative and six qualitative variables in a sample of 24 adult animals, 8 males and 16 females.Subsequently, investigation was made of the consanguinity of the individuals and of the population as well as the future influence of inbreeding in each generation. Finally, the accuracy and precision of the heterozygote-excess method was evaluated using two data sets from the Chato Murciano pig. One data set is an original population and the other is a F3+F4+F5 generation of a line created from mating a Chato Murciano female with a Large White boar as part of an absorption programme based on backcrosses with Chato Murciano boars.

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