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31.
Nest placement and nesting success in two finch species colonizing a recently established plantation in an arid region 总被引:1,自引:0,他引:1
This study examines variations in nest placement and its effects on nesting success in the Desert Finch (Rhodospiza obsoleta) and the Linnet (Carduelis cannabina) which coexist in a recently established plantation (novel habitat) in a desert region in Jordan. A comparison with other
habitats (old plantation in the desert and native, Mediterranean-type, habitat of the Linnet) showed that each species displayed
similarity in nest placement patterns across habitats. Nest concealment predicted nesting outcome in the Linnet, whereas nest
height predicted nesting outcome in the Desert Finch. Daily survival rates were significantly higher in Desert Finch nests
compared to the Linnet's, perhaps because Desert Finches placed nests higher in the novel habitat, which lacked aerial nest
predators. In accordance with predation theories of life history evolution, we provide evidence that variation in nest placement
among the two species in a novel habitat resulted from previous exposure to different predation risks. 相似文献
32.
Razzaq TM Bass R Vines DJ Werner F Whawell SA Ellis V 《The Journal of biological chemistry》2003,278(43):42679-42685
We have demonstrated that tissue plasminogen activator (tPA) binds specifically to human vascular smooth muscle cells (VSMC) in a functionally relevant manner, both increasing plasminogen activation and decreasing tPA inhibition (Ellis, V., and Whawell, S. A. (1997) Blood 90, 2312-2322; Werner, F., Razzaq, T. M., and Ellis, V. (1999) J. Biol. Chem. 274, 21555-21561). To further understand this system we have now identified and characterized the protein responsible for this binding. Rat VSMC were surface-labeled with 125I, and cell lysates were subjected to an affinity chromatography scheme based on the previously identified tPA binding characteristics. A single radiolabeled protein of 63 kDa bound specifically and was eluted at low pH. This protein was isolated from large scale preparations of VSMC and unambiguously identified as the rat homologue of the human type-II transmembrane protein p63 (CKAP4) by matrix-assisted laser desorption ionization and nano-electrospray tandem mass spectrometry of tryptic fragments. In confirmation of this, a monoclonal antibody raised against authentic human p63 recognized the isolated protein in Western blotting. Immunofluorescence microscopy demonstrated that p63 was located principally in the endoplasmic reticulum but was also detected in significant quantities on the surface of human VSMC. In support of the hypothesis that p63 is the functional tPA binding site on VSMC, an anti-p63 monoclonal antibody was found to block tPA binding. Furthermore, heterologous expression of an N-terminally truncated mutant of p63, which targets exclusively to the plasma membrane, led to an increase in tPA-catalyzed plasminogen activation. Therefore, p63 on the surface of VSMC may contribute to the functional regulation of the plasminogen activation system in the vessel wall. 相似文献
33.
M. Vanaja M. Maheswari P. Sathish P. Vagheera N. Jyothi Lakshmi G. Vijay Kumar S. K. Yadav Abdul Razzaq Jainender Singh B. Sarkar 《Physiology and Molecular Biology of Plants》2015,21(4):541-549
Three pigeonpea (Cajanus cajan L. Millsp.) genotypes- GT-1, AKP-1 and PRG-158 with varying crop duration, growth habit and flowering pattern were evaluated for variability in their response for drought stress. Drought stress was imposed at initiation of flowering and the observations on biomass and seed yield parameters were recorded at harvest. The magnitude of response of individual component to drought stress was found to be genotype specific. Drought stress significantly decreased photosynthetic rate (PN), transpiration rate (Tr) and relative water content (RWC) in all the genotypes, however the magnitude of reduction differed with genotype. With drought stress, the reduction of PN was highest in GT-1 while reduction in Tr was highest in PRG-158. The genotype AKP-1, accumulated significantly higher concentrations of osmotic solutes especially proline under water deficit stress, this facilitated it to maintain higher relative water content (RWC) and lower malondialdehyde (MDA) content as compared to other genotypes. Drought stress also impacted biomass production and their partitioning to vegetative and reproductive components at harvest. There was significant variability between the genotypes for seed yield under drought stress while it was non-significant under well-watered condition. Drought stress enhanced flower drop and decreased flower to pod conversion resulting in reduced pod number and seed number in PRG-158 and GT-1. The genotype AKP-1 recorded superior performance for seed yield under stress environment due to its ability in maintaining pod and seed number as well as improved test weight (100 seed weight). Under drought stress, significant positive association of seed yield with proline, seed number, pod number and test weight clearly indicating their role in drought tolerance. 相似文献
34.
Subramaniyam Ravichandran Maria Razzaq Nazia Parveen Ambarnil Ghosh Kyeong Kyu Kim 《Nucleic acids research》2021,49(18):10689
G-quadruplex (G4), a four-stranded DNA or RNA structure containing stacks of guanine tetrads, plays regulatory roles in many cellular functions. So far, conventional G4s containing loops of 1–7 nucleotides have been widely studied. Increasing experimental evidence suggests that unconventional G4s, such as G4s containing long loops (long-loop G4s), play a regulatory role in the genome by forming a stable structure. Other secondary structures such as hairpins in the loop might thus contribute to the stability of long-loop G4s. Therefore, investigation of the effect of the hairpin-loops on the structure and function of G4s is required. In this study, we performed a systematic biochemical investigation of model G4s containing long loops with various sizes and structures. We found that the long-loop G4s are less stable than conventional G4s, but their stability increased when the loop forms a hairpin (hairpin-G4). We also verified the biological significance of hairpin-G4s by showing that hairpin-G4s present in the genome also form stable G4s and regulate gene expression as confirmed by in cellulo reporter assays. This study contributes to expanding the scope and diversity of G4s, thus facilitating future studies on the role of G4s in the human genome. 相似文献
35.
Misbah Majid Akbar Masood Showkat Ahmad Kadla Iqra Hameed Bashir A. Ganai 《Biochemical genetics》2017,55(1):10-21
Type 2 diabetes mellitus (T2DM) is characterized by chronic hyperglycemia associated with insulin resistance and relative insulin deficiency. T2DM is believed to be attributable to the combined effect of genetic and environmental factors. Peroxisome proliferator-activated receptor gamma 2 (PPARγ2) is one of the main candidate genes that are implicated in T2DM. A common proline 12 alanine (Pro12Ala) polymorphism in PPARγ2 has been shown to be associated with T2DM. The aim of this work was to investigate the possible role of PPARγ2 gene polymorphism, as a genetic risk factor for T2DM. The study comprised 200 ethnic unrelated subjects (100 T2DM patients and 100 controls). PCR–RFLP technique was used for genotyping analysis. The frequency of the Pro allele was 79 and 91.5 % for controls and cases, respectively (P < 0.05; OR 3.2; 95 % CI 1.64–6.3). The Pro12Ala polymorphism was in Hardy–Weinberg equilibrium in both patients and controls (χ 2 = 0.13, P > 0.05). We found a significant association of Pro12Ala polymorphism of PPARγ2 gene with T2DM, however the genotypes showed statistically significant association only with few clinical parameters including body mass index, total cholesterol, and low-density lipoprotein (P < 0.05). The study signifies that Pro allele in PPARγ2 may be a genotypic risk factor that confers susceptibility to T2DM in ethnic Kashmiri population. 相似文献
36.
Sadaf Rafiq Z.A. Rather Reyaz Ahmad Bhat I.T. Nazki Mohammad S. AL-Harbi Neelofar Banday Iqra Farooq Bassem N. Samra M.H. Khan Atef F. Ahmed Najmah Andrabi 《Saudi Journal of Biological Sciences》2021,28(12):7581
Micropropagation protocol of Oriental Hybrid Lilium cv. Ravenna was developed using bulb scale segments (Basal and Tip) as explants. Surface sterilization of healthy bulb scales with carbendazim 200 ppm for 30 min, then 0.1 percent mercuric chloride for 10 min, then 70% ethyl alcohol for 30 s was superior to all other treatments in recording highest culture asepsis (77.08%) and higher explant survival (86.12%). Explant survival was higher in basal segments (88.54%) compared to tip segments (85.52%). Highest culture establishment was recorded in basal scale segments (68.26%) followed by tip scale segments (55.21%). MS medium augmented with 0.50 mgl−1 Naphthalene acetic acid and 2.0 mgl−1. 6-Benzylamino Purine recorded maximum culture establishment (76.17%), highest bulblet number/explant (5.52) with maximum length of shoots (2.20 cm) and number of leaves (3.39). This treatment combination of growth regulators resulted in highest shoot proliferation (83.33%) along with maximum shoot number (2.41explant−1), shoot length (2.35 cm) and leaf number (5.44) of micro shoots during proliferation stage. Rooting of explants was superior with Indole-3-butyric acid compared to Naphthalene acetic acid. Highest rooting of 92.71% along with maximum number of primary roots shoot−1 (12.06), maximum primary root length (3.17 cm) was documented in Murashige and Skoog medium added with Indole-3-butyric acid 1.50 mgl−1 with best ex vitro survival rate (98.96%) of rooted plantlets during primary hardening in perlite + vermiculite (1:1) mixture. 相似文献
37.
38.
Ujala Sehar Muhammad Aamer Mehmood Khadim Hussain Salman Nawaz Shahid Nadeem Muhammad Hussnain Siddique Habibullah Nadeem Munazza Gull Niaz Ahmad Iqra Sohail Saba Shahid Gill Summera Majeed 《Bioinformation》2013,9(18):901-907
This paper presents an in silico characterization of the chitin binding protein CBP50 from B. thuringiensis serovar konkukian S4
through homology modeling and molecular docking. The CBP50 has shown a modular structure containing an N-terminal
CBM33 domain, two consecutive fibronectin-III (Fn-III) like domains and a C-terminal CBM5 domain. The protein presented a
unique modular structure which could not be modeled using ordinary procedures. So, domain wise modeling using
MODELLER and docking analyses using Autodock Vina were performed. The best conformation for each domain was selected
using standard procedure. It was revealed that four amino acid residues Glu-71, Ser-74, Glu-76 and Gln-90 from N-terminal
domain are involved in protein-substrate interaction. Similarly, amino acid residues Trp-20, Asn-21, Ser-23 and Val-30 of Fn-III
like domains and Glu-15, Ala-17, Ser-18 and Leu-35 of C-terminal domain were involved in substrate binding. Site-directed
mutagenesis of these proposed amino acid residues in future will elucidate the key amino acids involved in chitin binding
activity of CBP50 protein. 相似文献
39.
Ujala Sehar Muhammad Aamer Mehmood Salman Nawaz Shahid Nadeem Khadim Hussain Iqra Sohail Muhammad Rizwan Tabassum Saba Shahid Gill Anam Saqib 《Bioinformation》2013,9(14):725-729
Bacillus thuringiensis is an insecticidal bacterium whose chitinolytic system has been exploited to improve insect resistance in crops.
In the present study, we studied the CBP24 from B. thuringiensis using homology modeling and molecular docking. The primary
and secondary structure analyses showed CBP24 is a positively charged protein and contains single domain that belongs to family
CBM33. The 3D model after refinement was used to explore the chitin binding characteristics of CBP24 using AUTODOCK. The
docking analyses have shown that the surface exposed hydrophilic amino acid residues Thr-103, Lys-112 and Ser-162 interact with
substrate through H-bonding. While, the amino acids resides Glu-39, Tyr-46, Ser-104 and Asn-109 were shown to have polar
interactions with the substrate. The binding energy values evaluation of docking depicts a stable intermolecular conformation of
the docked complex. The functional characterization of the CBP24 will elucidate the substrate-interaction pathway of the protein in
specific and the carbohydrate binding proteins in general leading towards the exploration and exploitation of the prokaryotic
substrate utilization pathways. 相似文献
40.
Shama Razzaq Asaad Ahmed Nafees Unaib Rabbani Muhammad Irfan Shahla Naeem Muhammad Arslan Khan Zafar Fatmi Peter Burney 《BMC pulmonary medicine》2018,18(1):184