SUMMARY / RELATED TOPICS

N-terminus

The N-terminus is the start of a protein or polypeptide referring to the free amine group located at the end of a polypeptide. The amine group is bonded to another carboxylic group in a protein to make it a chain, but since the end of a protein has only 1 out of 2 areas chained, the free amine group is referred to the N-terminus. By convention, peptide sequences are written N-terminus to C-terminus, left to right in LTR languages; this correlates the translation direction to the text direction. Each amino acid has a carboxylic group. Amino acids link to one another by peptide bonds which form through a dehydration reaction that joins the carboxyl group of one amino acid to the amine group of the next in a head-to-tail manner to form a polypeptide chain; the chain has two ends – an amine group, the N-terminus, an unbound carboxyl group, the C-terminus. When a protein is translated from messenger RNA, it is created from N-terminus to C-terminus; the amino end of an amino acid during the elongation stage of translation, attaches to the carboxyl end of the growing chain.

Since the start codon of the genetic code codes for the amino acid methionine, most protein sequences start with a methionine. However, some proteins are modified posttranslationally, for example, by cleavage from a protein precursor, therefore may have different amino acids at their N-terminus; the N-terminus is the first part of the protein. It contains signal peptide sequences, "intracellular postal codes" that direct delivery of the protein to the proper organelle; the signal peptide is removed at the destination by a signal peptidase. The N-terminal amino acid of a protein is an important determinant of its half-life; this is called the N-end rule. The N-terminal signal peptide is recognized by the signal recognition particle and results in the targeting of the protein to the secretory pathway. In eukaryotic cells, these proteins are synthesized at the rough endoplasmic reticulum. In prokaryotic cells, the proteins are exported across the cell membrane. In chloroplasts, signal peptides target proteins to the thylakoids.

The N-terminal mitochondrial targeting peptide allows the protein to be imported into the mitochondrion. The N-terminal chloroplast targeting peptide allows for the protein to be imported into the chloroplast. Protein N-termini can be modified co - or posttranslationally. Modifications include the removal of initiator methionine by aminopeptidases, attachment of small chemical groups such as acetyl and methyl, the addition of membrane anchors, such as palmitoyl and myristoyl groups N-terminal acetylationN-terminal acetylation is a form of protein modification that can occur in both prokaryotes and eukaryotes, it has been suggested that N-terminal acetylation can prevent a protein from following a secretory pathway. The N-terminus can be modified by the addition of a myristoyl anchor. Proteins that are modified this way contain a consensus motif at their N-terminus as a modification signal; the N-terminus can be modified by the addition of a fatty acid anchor to form N-acylated proteins. The most common form of such modification is the addition of a palmitoyl group.

TopFIND, a scientific database covering proteases, their cleavage site specificity, substrates and protein termini originating from their activity

Pazhani (1965 film)

Pazhani is a 1965 Indian Tamil-language drama film and directed by A. Bhimsingh and produced by A. P. Chinnappan; the film dialogue was written by M. S. Solaimani and story was written by G. V. Iyer respectively; the film features Sivaji Ganesan playing titular role, with other prominent actors S. S. Rajendran, R. Muthuraman, T. S. Balaiah and M. R. Radha in lead, with Devika, Pushpalatha and C. Lakshmi Rajyam playing a pivotal role; the film had musical score by Viswanathan–Ramamoorthy and was released on 14 January 1965. The film is a trend-setting film in Tamil Cinema on love and bonding among the siblings and how each of them support the other brothers, despite adversities; the film dwells on the need for farmers in villages to focus on cultivation instead of looking at city life. The film was a critical success and earned a certificate of appreciation from National Awards for its theme. Pazhani, a widowed farmer lives with his three younger brothers, Velu and Muthu and orphaned niece Kaveri.

The entire family toils on land leased from Chokkalingam and they lead a content life together. Velu's wicked wife Nagamma leaves him after a fight with the brothers. After much pacification by Pazhani, she returns to live in the nuclear family with her husband. Muthu likes a college student. Chokkalingam is a cunning and wicked person, encouraged by his accounts Kalyanam and Santhanam. Chokkalingam, who has an eye on Emily invites her home and tries to molest her and Muthu, who happens to be there rescues her, after beating Chokkalingam. Chokkalingam decides to take revenge on Pazhani's family. Pazhani and his brothers find a treasure and since it's Chokkalingam's land, they hand it over to him; the police investigate Chokkalingam and he shows a smaller pot of treasure. However, when Pazhani is interrogated, he states that it was a bigger pot of treasure, leading to a raid and seizure of the treasure in Chokkalingam's house. Chokkalingam in anger sells Pazhani pleads for mercy, but Chokkalingam pays no heed.

Meanwhile, Emily completes her leaves to Chennai and this saddens Muthu. Vino Bhave's Bhoodan Movements gains momentum in all villages and Chokkalingam generously 5 acres of rocky and barren land; the same land is donated by the organisers to a deserving Pazhani. Pazhani motivates his frustrated brothers to make the rocky and arid land fertile. Chokkalingam cunningly offers Rs. 2,000/- to Pazhani as a loan after obtaining his signature on a blank stamp paper for developing the land. A jealous Nagamma spreads a rumour that Chokkalingam favours the family because he is in a relationship with Kaveri. Pazhani announces the engagement of Kaveri and Raju. Furious, Nagamma poisons Pazhani's cow and Velu suspects Nagamma and while scolding her, he is bitten by a snake and dies. Nagamma reforms, shocked with the sudden demise of her husband; as per Velu's desire, the marriage of Raju and Kaveri takes place. It is harvest time and Chokkalingam sends his people to harvest at the land developed by Pazhani with his brothers.

Pazhani and his brothers are demand the reason. Chokkalingam shows borrowing of Rs. 12, 000/- on the stamp paper signed by Pazhani and states that since he did not repay the loan, he is harvesting to recover the dues. Pazhani is shocked at Chokkalingam's lies and deceit. Raju and Muthu leave the village. Kaveri decides to stay with Pazhani, devastated after losing his land and brothers. Raju and Muthu meet Emily at Chennai and with her help get a job and save money to buy land for their brother. Time passes and Raju and Muthu manage to save and convey this through a letter to Pazhani, but Gopal, a co-worker steals that money. An angry Raju is jailed for assault. Emily's mother dies and Muthu marries Emily. Pazhani, on receiving the letter comes to meet his brothers and gets shocked to know that Raju is jailed and Muthu is married. Dejected with life, he returns to the village. Meanwhile, Chokkalingam tries to molest Nagamma and she escapes. To take revenge, Chokkalingam brands her a prostitute and brands Kaveri, who comes to her support and they are excommunicated from the village.

Pazhani gets angry with the villagers and becomes insane. Raju, upon release goes to attack him. A scared Chokkalingam takes refuge in a temple. Pazhani's forgiving attitude reforms Chokkalingam and he apologises for his crime and surrenders to the Police. Meanwhile, Santhanam finds out; the lands are taken over by the cooperative society and distributed among the landless villagers, including Pazhani's family. Muthu returns to the village and everyone unites to work and reap the benefits. Sivaji Ganesan as Pazhani S. S. Rajendran as Raju, Pazhani's Second younger brother R. Muthuraman as Muthu, Pazhani's Third younger brother Devika as Kavery T. S. Balaiah as Chokkalingam Pannaiyar M. R. Radha as Kalyanam, Chokkalingam's Accountant Nagesh as Sandhanam, Chokkalingam Accountant Pushpalatha as Emily Sriram as Velu, Pazhani's First younger brother Karuppu Subbiah as Karuppiah The film does not have any artiste credit in the titles; the film presents a radical concept of how farmers should be in village and cultivate the lands so that city people will get the food.

The first Tamil film to present the concept of bonding and love among the siblings and the role of farmers in village. The film was a critical success and ran for 100 days and won a certificate at National Film Award for Best Feature Film in Ta

Nakh languages

The Nakh languages are a group of languages within Northeast Caucasian, spoken chiefly by the Chechens and Ingush in the North Caucasus within Southern Russia. Bats is the endangered language of an ethnic minority in Georgia; the Chechen and Bats peoples are grouped under the ethno-linguistic umbrella of Nakh peoples. The Nakh languages were classified as an independent North-Central Caucasian family, but are now recognized as a branch of the Northeast Caucasian family; the separation of Nakh from common Northeast Caucasian has been tentatively dated to the Neolithic. The Nakh language family consists of: Vainakh languages, a dialect continuum with two literary languages: Chechen – 1,330,000 speakers. Ingush – 413,000 speakers. Bats or Batsbi – 3,420, spoken in Zemo-Alvani, Georgia. Not mutually intelligible with Chechen or Ingush; the Nakh languages are relevant to the glottalic theory of Indo-European, because the Vainakh branch has undergone the voicing of ejectives, postulated but derided as improbable in that family.

In initial position, Bats ejectives correspond to Vainakh ejectives, but in non-initial position to Vainakh voiced consonants. A similar change has taken place in some of the other Dagestanian languages. Many obscure ancient languages or peoples have been postulated by scholars of the Caucasus as Nakh, many in the South Caucasus. None of these have been confirmed; the Èrsh language, language of the Èrs who inhabited Northern Armenia, later Hereti in Southeast Georgia and Northwest Azerbaijan. This is considered to be less confirmed as Nakh, they were assimilated and their language was replaced by Georgian or Azeri. The language of the Malkhs in the North Caucasus, who lived in modern day Kabardino-Balkaria, Karachay–Cherkessia, once conquered Ubykhia and Abkhazia, they were conquered first by Scythian-speaking Alan tribes and by Turkic tribes, seem to have abandoned their homeland and found shelter among the Chechens, leading to the formation of a teip named after them. Those who stayed behind assimilated.

The language of the Kakh, old inhabitants of Kakheti and Tusheti in Eastern Georgia. The Kakh called themselves Kabatsas and their territory Kakh-Batsa, they may or may not be ancestral to the modern Bats, they may or may not be related to them. They were assimilated by the Kartlians to speak Georgian. Gligvs, a mysterious people in the North Caucasus attributed by Georgian historians to be a Nakh people, they may be ancestral to the Ingush, but the term used by Georgians for the Ingush is "Kist", causing large amounts of confusion. The language of the Tsanars in historical Georgia is thought by many historians to be Nakh, based on place names, geographic location, other such information; the language of the Dvals is thought to be Nakh by many historians, though there is a rivaling camp arguing for its status as a close relative of Ossetic. Various backing for the Nakh theory includes the presence of Nakh placenames in former Dval territory, evidence of Nakh–Svan contact which would've required the Nakh nature of the Dvals or people there before them, the presence of a foreign-origin Dval clan among the Chechens implying that the Dvals found shelter among the Chechens from the conquest of their land by foreign invaders.

The Dvals were conquered by the Ossetes in the north. It is thought that Dval did not go extinct until the 18th century, making the Dvals the most recent Nakh people known to have died out. According to Georgian scholars I. A. Javashvili and Giorgi Melikishvili, the Urartian state of Supani was occupied by the ancient Nakh tribe Tsov, whose state is called Tsobena in ancient Georgian historiography; the Tsov language was the dominant language spoken by its people, was thought by these Georgian historians to be Nakh. Tsov and its relatives in the area may have contributed to the Hurro-Urartian substratum in the Armenian language. Languages of the Caucasus Northeast Caucasian languages North Caucasian languages Alarodian languages Proto-Nakh basic lexicon at the Global Lexicostatistical Database