Male reproductive success in harem troops of hanuman langurs (Presbytis entellus)

Based on cross-sectional and longitudinal data collected in 1967–1988 by various observers, male reproductive success was studied in the Hanuman langurs of Jodhpur, India. The harem-structured social organization ensures a high degree of paternity certainty. Births occur throughout the year, with significant peaks and minima in March and November, respectively (n =398).The interbirth interval averages 16.7 months (n = 114).The duration of harem residencies varies between 3 days and ≥ 74.0 months, with a mean of 26.5 (n = 64). Harem holder replacements occur during all months of the year. No male achieves residency in more than one troop, suggesting that residency is associated with a distinct peak in the resource holding potential of a given male. Reproductive success among males varies considerably. Male mortality is high due to migration and intrasexual competition, leading to an adult sex ratio of 1:4.9. It is estimated that one-quarter of all adult males will never gain harem residency. Conceptions achieved outside harem residencies are so rare (4.7%) that a viable low-risk strategy, opting for longevity instead of harem residency, is unlikely. Tenure length has a stronger influence on male reproductive success than harem size because interbirth intervals are significantly shorter in small harems than in larger ones. It is assumed that females in one-male breeding structures compete for sperm and that such competition is more intense in larger harems.     

Fate of ousted male residents of one-male bisexual troops of Hanuman langurs (Presbytis entellus) at Jodhpur,Rajasthan, India

Little is known about the fate of adult male residents after they are ousted from bisexual one-male troops of Hanuman langurs (Presbytis entellus) in the course of adult male replacements. In a long term study at Jodhpur, Rajasthan, it was possible to reconstruct partial life histories of several ousted residents. One resident was killed during the male change. Ousted residents did not regain residency despite their continued invasions into bisexual troops. It is assumed that the males' chances to take over and to defend a troop are restricted to an age of 9–14 years, when the males are in prime physical condition. One male became solitary for some months while trying to regain residency of his old troop, before joining some “alien” males. As a rule, males are likely to rejoin their own male bands if they are ousted after short periods of residency. If the residency exceeds 3 months then the ongoing structural change in the former band may prevent their reintegration. However, in such cases, ousted residents which belonged to the same band may reunite and mingle with another male band which lacks prime males. Weaned sons may follow their fathers after ousting. In the case of numerous weaned offspring, fathers and sons may together form at least temporary new male bands.     

In vivo andin vitro methylation of lysine residues ofEuglena gracilis histone H1

We have earlier identified and purified two protein-lysine N-methyltransferases (Protein methylase III) fromEuglena gracilis [J. Biol. Chem.,260, 7114 (1985)]. The enzymes were highly specific toward histone H1 (lysine-rich), and the enzymatic products were identified as -N-mono-, di- and trimethyllysines. These earlier studies, however, were carried out with rat liver histone H1 as thein vitro substrate. Presently, histone H1 has been purified fromEuglena gracilis through Bio-Rex 70 and Bio-Gel P-100 column chromatography. TheEuglena histone H1 showed a single band on SDS-polyacrylamide gel electrophoresis and behaved like other histone H1 of higher animals, whereas it had a much higherR _f value than the other histones H1 in acid/urea gel electrophoresis. When theEuglena histone H1 was [methyl-³H]-labeledin vitro by a homologous enzyme (one of the twoEuglena protein methylase III) and analyzed on two-dimensional gel electrophoresis, three distinctive subtypes of histone H1 were shown to be radiolabeled, whereas five subtypes of rat liver histone H1 were found to be labeled. Finally, by the combined use of a strong cation exchange and reversed-phase Resolve C₁₈ columns on HPLC, we demonstrated thatEuglena histone H1 contains approximately 9 mol% of -N-methyllysines (1.40, 1.66, and 5.62 mol% for -N-mono-, di- and trimethyllysines, respectively). This is the first demonstration of the natural occurrence of -N-methyllysines in histone H1.     

In vivo andin vitro methylation of lysine residues ofEuglena gracilis histone H1

We have earlier identified and purified two protein-lysine N-methyltransferases (Protein methylase III) fromEuglena gracilis [J. Biol. Chem.,260, 7114 (1985)]. The enzymes were highly specific toward histone H1 (lysine-rich), and the enzymatic products were identified as ε-N-mono-, di- and trimethyllysines. These earlier studies, however, were carried out with rat liver histone H1 as thein vitro substrate. Presently, histone H1 has been purified fromEuglena gracilis through Bio-Rex 70 and Bio-Gel P-100 column chromatography. TheEuglena histone H1 showed a single band on SDS-polyacrylamide gel electrophoresis and behaved like other histone H1 of higher animals, whereas it had a much higherR _f value than the other histones H1 in acid/urea gel electrophoresis. When theEuglena histone H1 was [methyl-³H]-labeledin vitro by a homologous enzyme (one of the twoEuglena protein methylase III) and analyzed on two-dimensional gel electrophoresis, three distinctive subtypes of histone H1 were shown to be radiolabeled, whereas five subtypes of rat liver histone H1 were found to be labeled. Finally, by the combined use of a strong cation exchange and reversed-phase Resolve C₁₈ columns on HPLC, we demonstrated thatEuglena histone H1 contains approximately 9 mol% of ε-N-methyllysines (1.40, 1.66, and 5.62 mol% for ε-N-mono-, di- and trimethyllysines, respectively). This is the first demonstration of the natural occurrence of ε-N-methyllysines in histone H1.     

Survival of phosphate-solubilizing bacteria against DNA damaging agents

Phosphate-solubilizing bacteria (PSBs) were isolated from different plant rhizosphere soils of various agroecological regions of India. These isolates showed synthesis of pyrroloquinoline quinone (PQQ), production of gluconic acid, and release of phosphorus from insoluble tricalcium phosphate. The bacterial isolates synthesizing PQQ also showed higher tolerance to ultraviolet C radiation and mitomycin C as compared to Escherichia coli but were less tolerant than Deinococcus radiodurans. Unlike E. coli, PSB isolates showed higher tolerance to DNA damage when grown in the absence of inorganic phosphate. Higher tolerance to ultraviolet C radiation and oxidative stress in these PSBs grown under PQQ synthesis inducible conditions, namely phosphate starvation, might suggest the possible additional role of this redox cofactor in the survival of these isolates under extreme abiotic stress conditions.     

南方4种草本植物对铝胁迫生理响应的研究

 不同的植物对铝胁迫的生理响应不同, 因而对铝毒的耐性也不相同。设置5种铝浓度,进行砂培法处理,研究了4种我国南方红壤广泛分布的草本植物——牵牛(Pharbitis nil)、望江南(Cassia occidentlis)、光头稗(Echinochloa colonum)和合萌(Aeschynomene indica)的种子萌发、光合色素、脯氨酸含量、丙二醛(MDA)含量、可溶性糖(SS)含量、质膜透性(MP)、过氧化氢酶 (CAT) 活性以及过氧化物酶 (POD)活性的变化。结果表明铝对4种植物的生理特性都有明显的影响。4种植物的种子在10 000 mg·L－1 Al3+处理条件下都不能萌发。2 000 mg·L－1 Al3+处理都不利于4种植物的生长,与对照相比,2 000 mg·L－1 Al3+处理时4种草本植物叶绿素和叶绿素总含量显著降低(p<0.05);MDA含量和MP显著增加(p<0.05);脯氨酸含量极显著增加(p<0.01);POD和CAT活性极显著降低(p<0.01)。中低铝(80和400 mg·L－1)处理时,牵牛和合萌与对照相比,MP和MDA含量降低,POD和CAT活性升高;望江南的反应与牵牛和合萌的反应相反;光头稗在80 mg·L－1 Al3+处理时,与牵牛和合萌的变化一致,在400 mg·L－1 Al3+处理时,则相反。植物在中低铝处理条件下,通过维持较高的POD和CAT活性和脯氨酸、叶绿素含量,较低的MP和MDA含量来增加其对铝的耐性。     

Structural and biophysical properties of h-FANCI ARM repeat protein

Fanconi anemia complementation groups – I (FANCI) protein facilitates DNA ICL (Inter-Cross-link) repair and plays a crucial role in genomic integrity. FANCI is a 1328 amino acids protein which contains armadillo (ARM) repeats and EDGE motif at the C-terminus. ARM repeats are functionally diverse and evolutionarily conserved domain that plays a pivotal role in protein–protein and protein–DNA interactions. Considering the importance of ARM repeats, we have explored comprehensive in silico and in vitro approach to examine folding pattern. Size exclusion chromatography, dynamic light scattering (DLS) and glutaraldehyde crosslinking studies suggest that FANCI ARM repeat exist as monomer as well as in oligomeric forms. Circular dichroism (CD) and fluorescence spectroscopy results demonstrate that protein has predominantly α- helices and well-folded tertiary structure. DNA binding was analysed using electrophoretic mobility shift assay by autoradiography. Temperature-dependent CD, Fluorescence spectroscopy and DLS studies concluded that protein unfolds and start forming oligomer from 30°C. The existence of stable portion within FANCI ARM repeat was examined using limited proteolysis and mass spectrometry. The normal mode analysis, molecular dynamics and principal component analysis demonstrated that helix-turn-helix (HTH) motif present in ARM repeat is highly dynamic and has anti-correlated motion. Furthermore, FANCI ARM repeat has HTH structural motif which binds to double-stranded DNA.     

Involvement of a protein kinase activity inducer in DNA double strand break repair and radioresistance of Deinococcus radiodurans

Transgenic bacteria producing pyrroloquinoline quinone, a known cofactor for dehydrogenases and an inducer of a periplasmic protein kinase activity, show resistance to both oxidative stress and protection from nonoxidative effects of radiation and DNA-damaging agents. Deinococcus radiodurans R1 encodes an active pyrroloquinoline quinone synthase, and constitutive synthesis of pyrroloquinoline quinone occurred in wild-type bacteria. Disruption of a genomic copy of pqqE resulted in cells that lacked this cofactor. The mutant showed a nearly 3-log decrease in gamma radiation resistance and a 2-log decrease in mitomycin C tolerance compared to wild-type cells. The mutant cells did not show sensitivity to UVC radiation. Expression of pyrroloquinoline quinone synthase in trans showed that there was functional complementation of gamma resistance and mitomycin C tolerance in the pqqE mutant. The sensitivity to gamma radiation was due to impairment or slow kinetics of DNA double strand break repair. Low levels of (32)P incorporation were observed in total soluble proteins of mutant cells compared to the wild type. The results suggest that pyrroloquinoline quinone has a regulatory role as a cofactor for dehydrogenases and an inducer of selected protein kinase activity in radiation resistance and DNA strand break repair in a radioresistant bacterium.